AIR BAG RESTRAINT SYSTEM

Article Text
1996 Dodge Ram Van B2500
For 1
Copyright © 1998 Mitchell Repair Information Company, LLC
Monday, July 30, 2012 04:25PM

ARTICLE BEGINNING

1996 ACCESSORIES/SAFETY EQUIPMENT

Chrysler Corp. & Mitsubishi Air Bag Restraint System

Dodge; Ram Van/Wagon

* PLEASE READ THIS FIRST *

WARNING: To avoid injury from accidental air bag deployment, read and
carefully follow all WARNINGS and SERVICE PRECAUTIONS.

DESCRIPTION & OPERATION

Ram Van and Ram Wagon are equipped with a driver-side air bag
only. SRS provides increased accident protection for driver by
deploying air bag in a front-end collision. A driver-side seat belt
pretensioner is an integral part of the system. The system deploys in
about 1/10th of a second after front impact sensors close.
System consists of an AIR BAG warning light, clockspring,
driver-side air bag module, Air Bag Control Module (ACM),impact sensor
and seat belt pretensioner device. The ACM monitors system, stores
fault codes (messages), and provides information to AIR BAG warning
light and ACM data link connector. A fault code is stored when AIR BAG
warning light is activated for more than 10 seconds.
One impact sensor is used in air bag system. Sensor is
located inside of ACM. Impact sensor is an accelerometer that senses
deceleration. When an impact is severe enough to require air bag
protection, deceleration pulses are sent to a microprocessor located
within the ACM. The ACM then sends a signal that completes the
electrical circuit through driver and passenger-side air bags. This
causes inflators to be actuated, producing a large quantity of
nitrogen gas and inflating air bags.

AIR BAG WARNING LIGHT

Whenever ignition switch is in RUN or START position, AIR BAG

warning light on instrument panel will glow for 6-8 seconds and then
turn off. This signifies ACM has performed a system self-check and
found SRS to be functioning properly. If AIR BAG warning light glows
for 10 seconds or more, stays on at all times, or does not come on, a
system malfunction exists.

IMPACT SENSORS

One impact sensor is used. Impact sensor is located within

ACM. Impact sensor is an accelerometer that senses deceleration. If
impact is severe enough, electrical circuit to air bags is completed.

AIR BAG MODULE

 The driver-side air bag module is mounted on front face of
steering wheel. The module's inflator assembly produces nitrogen gas
to fill air bag. When a small amount of current from ACM is applied,
initiator assembly starts a thermal reaction that spreads an ignitor
charge.
Surrounding ignitor charge, is a pellet-filled canister,
which produces nitrogen gas. Gas pressure builds and discharges from
inflator through a diffuser and screen assembly, forcing steering
wheel cover and instrument panel cover to burst along their seams
until air bags are fully inflated. Once air bags are fully inflated,
gas escapes through vents located on back of bag.

SEAT BELT PRETENSIONER

Integral with the driver-side air bag system, the seat belt
pretensioner is an electronically deployed pyrotechnic device
contained within driver-side seat belt retractor unit. When supplied
with the proper electrical signal, the device tightens the seat belt
to further restrain the driver in case of frontal impact. The device
is deployed by the air bag control module at the same time and under
the same conditions as the driver-side air bag module.

AIR BAG CONTROL MODULE (ACM)

ACM is mounted under driver's seat. Impact sensor (safing

sensor) is an integral part of ACM. The ACM monitors critical input
and output circuits within air bag system, ensuring they are operating
correctly. Some circuits are tested continuously; others are checked
only under certain conditions. The ACM provides information about air
bag system through AIR BAG warning light and ACM data link connector.
A fault code (message) is stored whenever AIR BAG warning light stays
on for 12 seconds or more.
ACM contains a capacitor which acts as a back-up power
supply. In the event that battery power is lost during a front end
collision, back-up power supply is able to deploy air bags for up to 2
minutes after disconnection.

ACM DATA LINK CONNECTOR

ACM data link connector (also known as DRB connector) is

located under lower left side of instrument panel. Data link connector
is used to access SRS on-board diagnostics.

CLOCKSPRING

Clockspring connects air bag module to steering column

wiring, completing SRS circuit. Inside clockspring is a flat, ribbon-
like tape of conductive material, which winds and unwinds with
steering wheel movement. Clockspring is most fragile part of air bag
system. Clockspring must be centered properly to allow 2 1/2 steering
wheel turns in either direction. Failure to align clockspring properly
may cause binding or premature clockspring failure. Copyright © 1998 Mitchell Repair Info
AIR BAG RESTRAINT SYSTEM Article Text (p. 2) 1996 Dodge Ram Van B2500For 1
 SHORTING BAR

Shorting bar is a device internal to initiator's (squib)

connectors that automatically shorts squib terminals when connector is
disconnected.

SYSTEM OPERATION CHECK

CAUTION: When battery is disconnected, vehicle computer and memory

systems may lose memory data. Driveability problems may
exist until computer systems have completed a relearn cycle.
See COMPUTER RELEARN PROCEDURES in GENERAL
INFORMATION before disconnecting battery.

NOTE: For DRB usage, see ENTERING ON-BOARD DIAGNOSTICS.

1) Disconnect negative battery cable, and tape cable end.

Connect DRB to ACM data link connector. ACM data link connector is
located under lower left side of instrument panel.
2) Install latest version of proper DRB cartridge. Turn
ignition on. Exit vehicle with DRB. After ensuring no one is inside
vehicle, reconnect negative battery cable.
3) Using DRB, read and record active fault codes. Read and
record any stored fault codes. Erase stored fault codes if there are
no active fault codes. If problem remains, fault codes will not erase.
Turn ignition off.
4) Turn ignition on again and observe AIR BAG warning light.
AIR BAG warning light should come on for 6-8 seconds, then go out,
indicating system is functioning properly. If AIR BAG warning light
either fails to illuminate, or comes on and stays on, a system
malfunction exists. Perform self-diagnostics. See DIAGNOSIS & TESTING.

SERVICE PRECAUTIONS

These precautions should be observed when working with air

bag systems:

* Disable air bag system before servicing any air bag system
or steering column component. Failure to do this could
result in accidental air bag deployment and possible
personal injury. See DISABLING & ACTIVATING AIR BAG SYSTEM.
* Back-up power supply maintains deployment voltage for about
2 minutes after battery is disconnected. When disabling air
bag system, always wait at least 2 minutes after
disconnecting battery cables to resume procedure.
* After repairs, ensure AIR BAG warning light works
properly and no system faults are indicated. See
SYSTEM OPERATION CHECK.
* Always wear safety glasses when servicing or AIR
handling
BAGanRESTRAINT SYSTEM Article Text (p. 3)1996 Dodge Ra
air bag.
* All SRS component fasteners are specially coated and are
designed with a specific function. Never replace SRS
component fasteners with other than original equipment parts.
* Air bag module must be stored in its original special
container until used for service. It must be stored in a
clean, dry, place, away from sources of extreme heat, sparks
and high electrical energy.
* When placing a live air bag on a bench or other surface,
always face air bag and trim cover up, away from surface.
This will reduce motion of module if accidentally deployed.
* After deployment, air bag surface may contain deposits of
sodium hydroxide, which irritates skin. Always wear safety
glasses, rubber gloves, and long-sleeved shirt during
clean-up and wash hands using mild soap and water. Follow
correct disposal procedures. See DISPOSAL PROCEDURES.
* Because of critical system operating requirements, DO NOT
attempt to service any air bag components. Corrections are
only made by replacing defective part.
* Electrical sources should never be allowed near inflator on
back of air bag module.
* When carrying a live air bag module, trim cover should be
pointed away from your body to minimize injury in case of
deployment.
* When testing voltage or continuity at Air Bag Control Module
(ACM), use wire side (not terminal end) of connector.
* DO NOT probe a wire through insulator, as this will damage
it and eventually cause failure.
* Replace clockspring whenever driver-side air bag deploys.
* When performing electrical tests, prevent accidental
shorting of terminals. Such shorts can damage fuses or
components and may cause a second fault code to set, making
diagnosis of original problem more difficult.
* When diagnosing air bag system, use DRB volt/ohm meter
unless instructed to use an external volt/ohm meter. NEVER
use an analog volt/ohm meter or test light in place of a
digital volt/ohm meter.
* When using DRB to diagnose an air bag system problem,
operate DRB from outside of vehicle. DO NOT sit inside of
vehicle.
* Never use an ohm meter to measure resistance of air bag
module. Accidental air bag deployment may occur, causing
personal injury.
* If air bag system is not fully functional for any reason,
vehicle should not be driven until system is repaired and
again becomes operational. DO NOT remove bulbs, modules,
sensors, or other components or in any way disable system
from operating normally. If air bag system is not
functional, park vehicle until it is repaired and functions
properly.
* When battery is disconnected, vehicle computer and memory
systems may lose memory data. Driveability problems may
exist until computer systems have completed a relearn cycle.
AIR BAG RESTRAINT SYSTEM Article Text (p. 4)1996 Dodge Ram Van B2500For 1 Copyright © 1998 Mit
 See COMPUTER RELEARN PROCEDURES in GENERAL INFORMATION
before disconnecting battery.

DISABLING & ACTIVATING AIR BAG SYSTEM

WARNING: Wait at least 2 minutes after disconnecting negative battery

cable before servicing air bag system. System reserve
capacitor, integral to ACM, maintains air bag system voltage
for about 2 minutes after battery is disconnected. Servicing
air bag system before 2 minutes may cause accidental air bag
deployment and possible personal injury.

CAUTION: When battery is disconnected, vehicle computer and memory

systems may lose memory data. Driveability problems may
exist until computer systems have completed a relearn cycle.
See COMPUTER RELEARN PROCEDURES in GENERAL INFORMATION
before disconnecting battery.

1) To disable air bag system for repairs, ensure ignition

switch is in OFF position. Disconnect negative battery cable and
insulate cable end with electrical tape. Wait at least 2 minutes after
disconnecting negative battery cable before servicing air bag system.
2) To activate air bag system, reconnect negative battery
cable. Turn ignition on. Observe AIR BAG warning light. Warning light
should come on for 6-8 seconds and then go out, indicating system is
functioning properly. If warning light fails to glow or glows and
stays on, a system malfunction exists. See SYSTEM OPERATION CHECK.

DISPOSAL PROCEDURES

DEPLOYED AIR BAG

WARNING: Vehicle interior will contain sodium hydroxide powder, a

by-product of air bag deployment. Since this powder can
irritate skin, eyes, nose, or throat, be sure to wear safety
glasses, rubber gloves, and long-sleeved shirt during
clean-up.

1) Take measures to avoid breathing powder produced during

air bag deployment. Place a piece of tape over air bag vent hole to
prevent additional powder spillage. Remove driver-side air bag module.
Use vacuum cleaner to remove residual powder from A/C-heater outlets
and vehicle interior.
2) Turn the blower motor to low for a few minutes and exit
the vehicle. Turn blower off. Vacuum any other powder expelled from
the plenum. Vacuum interior a second time to recover all powder. Avoid
kneeling or sitting on uncleaned surfaces. Dispose of deployed air
bags as any other part.

POST-COLLISION INSPECTION
AIR BAG RESTRAINT SYSTEM Article Text (p. 5)
 When a vehicle has been involved in a collision, certain
components of the passive restraint system must be inspected or
replaced. See PASSIVE RESTRAINT SYSTEM INSPECTION article in the
GENERAL INFORMATION section for post-collision inspection information.

REMOVAL & INSTALLATION

* PLEASE READ THIS FIRST *

WARNING: Failure to follow air bag service precautions may

result in air bag deployment and personal injury. See
SERVICE PRECAUTIONS. After component replacement,
ensure proper system operation. See SYSTEM OPERATION CHECK.

CAUTION: When battery is disconnected, vehicle computer and memory

systems may lose memory data. Driveability problems may
exist until computer systems have completed a relearn cycle.
See COMPUTER RELEARN PROCEDURES in GENERAL INFORMATION
before disconnecting battery.

CLOCKSPRING

WARNING: If air bag(s) have deployed, vehicle interior will contain

sodium hydroxide powder, a by-product of air bag deployment.
Since this powder can irritate skin, eyes, nose, and throat,
wear safety glasses, rubber gloves, and long-sleeved shirt
during clean-up. See DEPLOYED AIR BAG.

Removal
1) If replacing a deployed air bag, clockspring must be
replaced. Before proceeding, see SERVICE PRECAUTIONS. Set steering
wheel and front wheels in straight ahead position. Disable air bag
system. See DISABLING & ACTIVATING AIR BAG SYSTEM.
2) Clockspring is located behind steering wheel. See Fig. 1.
Remove air bag module and steering wheel. See
DRIVER-SIDE AIR BAG MODULE & STEERING WHEEL. Disconnect horn
connector. Remove cruise control switch and connector (if equipped).
Remove upper and lower steering column shrouds to gain access to
clockspring wiring.

AIR BAG RESTRAINT SYSTEM Article Text (p. 6)1996 Dodge Ram Van B2500For 1 Copyright © 1998 Mitchell Repair Info
Fig. 1: Identifying Clockspring
Courtesy of Chrysler Corp.

3) Disconnect 2-way clockspring harness connector, between

clockspring and instrument panel wiring harness, at base of steering
column.
4) Remove clockspring by releasing 2 tabs on side of
clockspring. Clockspring cannot be repaired and must be replaced if
faulty.BAG RESTRAINT SYSTEM Article Text (p. 7)1996 Dodge Ram Van B2500For 1
AIR Copyright © 1998 Mitchell Repair Info

Installation
1) Snap clockspring onto steering column. If clockspring
centering adjustment is disturbed, adjust clockspring. See CLOCKSPRING
. Connect clockspring wiring connectors.
Install steering column covers.
2) Install steering wheel. Ensure flats on steering wheel hub
fit formations on inside of clockspring. Pull horn wire through small
upper hole and clockspring and cruise control wires (if equipped)
through larger bottom hole in steering wheel. See Fig. 1.
3) Connect horn and cruise control wires (if equipped).
Connect clockspring wire to air bag module. To ensure complete
connector connection, latching arms must be visible on top of
connector housing. DO NOT connect negative battery cable at this time.
Perform system operation check to ensure system is functioning
properly. See SYSTEM OPERATION CHECK.

Fig. 2: Removing Driver-Side Air Bag Module (Typical)

Courtesy of Chrysler Corp.

DRIVER-SIDE AIR BAG MODULE & STEERING WHEEL

NOTE: Clockspring must be replaced whenever replacing a deployed

driver-side air bag. See CLOCKSPRING.

Removal
1) Before proceeding, see SERVICE PRECAUTIONS section.
Disable air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM.
2) Driver-side air bag module is mounted on face of steering
wheel. See Fig. 2. Position wheels in straight ahead position. Remove
cruise control switches (if equipped) and covers from steering wheel
back shroud, and disconnect wires.
3) Remove air bag module retaining bolts/nuts from rear of
steering wheel. Lift air bag module from steering wheel, and
disconnect electrical connector. Remove air bag module. Using Puller
(C3428B), remove steering wheel.

Installation
1) If replacing a deployed air bag module, replace
clockspring. See CLOCKSPRING. Position steering wheel on steering
column. Ensure flats on steering wheel hub fit formations on inside
AIRof BAG RESTRAINT SYSTEM Article Text (p. 8)
clockspring.
2) Ensure wires do not get pinched under steering wheel.
Install steering wheel retaining nut and tighten to specification. See
TORQUE SPECIFICATIONS.
3) Connect air bag module wire to air bag module. Install air
bag module, and tighten bolts to specification. Connect cruise control
wires to switches. Install switches.

SEAT BELT PRETENSIONER

WARNING: If air bag(s) have deployed, vehicle interior will contain

sodium hydroxide powder, a by-product of air bag deployment.
Since this powder can irritate skin, eyes, nose, and throat,
wear safety glasses, rubber gloves, and long-sleeved shirt
during clean-up. See DEPLOYED AIR BAG.

WARNING: After a collision in which driver-side air bag has been

deployed, the driver-side retractor is permanently locked
and must be replaced. A Yellow warning label is located on
inboard side of shoulder belt under upper anchor bolt cover.
If vehicle has been involved in a collision and Yellow label
is exposed, the seat/shoulder belt must be replaced.

Removal
1) Before proceeding, see SERVICE PRECAUTIONS.
Disable air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM.
2) If necessary move front seat all the way forward for
access to anchor bolts. Remove upper anchor bolt cover. Remove upper
anchor bolt, turning loop and anti-rattle washer. Remove push-in
fastener from seat belt retractor cover. See Fig. 3.
3) Separate cover from B-pillar. Remove seat belt retractor
anchor bolt from B-pillar. Separate seat belt retractor from vehicle.
Disconnect wire harness connector. Remove shoulder belt and retractor
from vehicle. See Fig. 4.

Fig. 3: Removing Upper Anchor Bolt Cover

Courtesy of Chrysler Corp.

AIR BAG RESTRAINT SYSTEM Article Text (p. 9

Fig. 4: Removing Seat Belt Retractor
Courtesy of Chrysler Corp.

Installation
Position upper end of turning loop at roof panel. To complete
installation, reverse removal procedure. Ensure retractor wire harness
does not interfere with operation of retractor or shoulder belt
travel. Tighten anchor bolt to specification. See
TORQUE SPECIFICATIONS.

AIR BAG
AIR BAG CONTROLSYSTEM
RESTRAINT MODULE (ACM)
Article Text (p. 10)1996 Dodge Ram Van B2500For 1 Copyright © 1998 Mitchell Repair In

WARNING: ACM contains safing sensor, which enables SRS to activate

 air bag. To prevent air bag deployment, DO NOT connect ACM
electrically to system if vehicle battery is connected.

Removal
1) Before proceeding, read air bag service precautions
section. See SERVICE PRECAUTIONS. Disable air bag system. See
DISABLING & ACTIVATING AIR BAG SYSTEM.
2) ACM is located under driver's seat. Disconnect wiring to
power seat and seat belts. Remove driver's seat.
3) Disconnect ACM connectors. Remove ACM retaining screws,
and remove ACM from the vehicle.

Installation
1) Install ACM with arrow pointing toward front of vehicle.
Install module screws, and tighten to specification. See
TORQUE SPECIFICATIONS. Connect electrical connectors.
2) To complete installation, reverse removal procedure. DO
NOT connect negative battery cable at this time. Ensure system is
functioning properly. See SYSTEM OPERATION CHECK.

ADJUSTMENTS

CLOCKSPRING CENTERING

CAUTION: If rotating part of clockspring is not positioned properly

with steering column and front wheels, clockspring failure
may result. Use following procedure to center clockspring.

1) Before proceeding, see SERVICE PRECAUTIONS. Disable air

bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM.
2) With steering wheel removed, depress 2 plastic auto-
locking tabs to release locking mechanism. See Fig. 1.
3) Keeping locking mechanism disengaged, rotate clockspring
rotor clockwise to end of its travel. DO NOT apply excessive torque.
From end of its travel, rotate rotor 2 1/2 turns in counterclockwise
direction.
4) Horn wire should end up at top and air bag module wire
(squib wire) at bottom. See Fig. 1. Engage clockspring locking
mechanism.
5) DO NOT connect negative battery cable at this time.
Perform system operation check to ensure system is functioning
properly. See SYSTEM OPERATION CHECK.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS TABLE

Application Ft. Lbs. (N.m)

Steering Wheel Nut ............................... 45 (61)

INCH Lbs. (N.m) AIR BAG RESTRAINT SYSTEM Article Text (p

Air Bag Control Module Screws/Nuts .............. 65 (7.5)
Driver-Side Air Bag Module Screws .......... 80-100 (9-11)
Seat Belt Retractor Anchor Bolts ................ 350 (40)

DIAGNOSIS & TESTING

* PLEASE READ THIS FIRST *

WARNING: Always follow air bag service precautions to avoid

air bag deployment and possible personal injury. See
SERVICE PRECAUTIONS. After component replacement,
ensure proper system operation. See SYSTEM OPERATION CHECK.

CAUTION: When battery is disconnected, vehicle computer and memory

systems may lose memory data. Driveability problems may
exist until computer systems have completed a relearn cycle.
See COMPUTER RELEARN PROCEDURES in GENERAL INFORMATION
before disconnecting battery.

NOTE: Although other readout boxes are available, manufacturer

recommends using Diagnostic Readout Box (DRB) tester to
access SRS on-board diagnostics. Following diagnosis and
testing procedures are designed for use with DRB.

SELF-DIAGNOSTIC SYSTEM

SRS is monitored by Air Bag Control Module (ACM). ACM

contains safing sensor, an integral sensor in circuitry of system,
which is used to fire air bag modules.
ACM monitors critical input and output circuits within air
bag system, ensuring they operate correctly. Some circuits are tested
continuously; others are checked under certain circumstances. ACM
provides information about air bag system, through AIR BAG warning
light and DRB. Each circuit monitored by ACM has a corresponding fault
code (message) assigned to it. For a description of fault codes, see
DIAGNOSTIC FAULT CODES (MESSAGES).

Active Codes
Active codes are hard codes and are accessed through DRB. If
a malfunction is detected, AIR BAG warning light remains on until
service is performed. Active fault codes are stored in ACM memory
after ignition switch is cycled. Active fault messages automatically
erase when fault is corrected.

Stored Codes
Stored codes are intermittent codes and are accessed through
DRB. If code is intermittent, AIR BAG warning light glows for 12
seconds or more and then goes out. Intermittent fault codes are stored
in ACM memory, along with number of times code was active and number
of key cycles fault was in memory. Minimum time stored for any code is
AIR BAG RESTRAINT SYSTEM Article Text (p. 12)1996 Dodge Ram Van
one minute. Stored codes will not automatically erase. DRB is required
to erase codes.

Erase Stored Codes

Erase stored codes feature is also useful as a diagnostic
tool. It is impossible to erase a stored code until cause of code is
corrected.

Intermittent Codes
If fault code is intermittent and malfunction is not present,
problem may not be located while performing diagnostic tests. In this
case, stored code can only suggest an area to inspect. If SAFING
SENSOR OPEN, SAFING SENSOR SHORT, INTERNAL DIAGNOSTIC #1, #2, #3, or
#4, LOW STORED ENERGY PASSENGER or LOW STORED ENERGY DRIVER fault
codes set intermittently, ACM should be replaced.
If any other intermittent codes set, check for loose or
corroded connections, damaged components, and damaged wiring. If no
obvious problems are found, erase stored codes. With ignition on,
wiggle wiring harness and connectors. Recheck for codes periodically
as you work through system. This procedure may uncover a difficult
problem to locate.

PRETEST INSPECTION & DIAGNOSTIC PROCEDURE

Following precautions and procedures must be followed:

* Always follow air bag service precautions to avoid

air bag deployment and possible personal injury. See
SERVICE PRECAUTIONS.
* After component replacement, ensure proper system operation.
See SYSTEM OPERATION CHECK.
* When testing voltage or continuity at ACM, use terminal side
(not wire end) of connector. DO NOT probe wire through
insulation.
* Always check if any TECH SERVICE BULLETINS (TSBs) apply to
vehicle.
* When using diagnostic charts, DO NOT skip any steps in chart
or incorrect diagnosis may result. Always start at TEST
1A - TESTING SYSTEM FUNCTION. Starting with any other test
may result in incorrect diagnosis. For description of fault
codes, see DIAGNOSTIC FAULT CODES (MESSAGES).
* Always use most current diagnostic program cartridge
available to prevent erroneous codes or test results.
* When using diagnostic charts, use DRB volt meter unless
instructed to use an external volt meter. Never use a test
light in place of a volt meter.
* When performing electrical tests, prevent accidental
shorting of terminals. Such shorts can damage fuses or
components and may cause a second code to be set, making
diagnosis of original problem more difficult.
* Vehicle must have a fully-charged battery and functional
charging system.
AIR BAG RESTRAINT SYSTEM Article Text (p
 * Each time a connector is disconnected, inspect it to ensure
it is in good condition. Always focus on circuit being
tested. Dirt, water and corrosion, are most common problems
in connectors.
* Always disconnect DRB after use.
* Always disconnect DRB before charging battery.

DRB KEYPAD FUNCTIONS

YES Or DOWN Arrow & NO Or UP Arrow Keys

Keys will move lines on screen up or down, allowing
technician to choose an item or scroll through all selections
available.

F1 & F2 Keys
Used to scroll through sensor displays.

ATM Key
Returns technician to previous screen.

ENTER Key
Allows technician to select a test or display. Flashing arrow
must be on desired display. Pressing ENTER key in sensor state will
change display from a 3-line display to a 1-line display.

F3 Key
Displays a help screen and may be used at any time.

Number Keys
Allows technician to choose a display or test by number
corresponding to test or display.

READ/HOLD Key
Freezes any sensor display.

MODE & ATM Keys

Pressing MODE and ATM keys at same time causes DRB to reset
to copyright screen.

ENTERING ON-BOARD DIAGNOSTICS

1) Before entering on-board diagnostics, refer to

PRETEST INSPECTION & DIAGNOSTIC PROCEDURE. Turn ignition off. Attach
most current DRB cartridge. DRB cartridge has ability to check itself
and DRB. It provides a volt/ohm meter and performs any test required
by air bag system diagnostics.
2) Connect DRB to ACM data link connector. ACM data link
connector (also known as DRB connector) is located under lower left
side of instrument panel. Ensure all accessories are off. Turn
ignition on. All character positions will glow, and copyright
information will appear on screen for a few seconds. Display will then
change to DRB menu. AIR BAG RESTRAINT SYSTEM Article Text (p. 14)1996 Dodge Ram Van B2500For 1
 3) If DRB displays error message, see DRB ERROR MESSAGES.
Following modes are accessible from DRB menu: VEHICLES TESTED, HOW TO
USE, CONFIGURE and SELECT SYSTEM.

VEHICLES TESTED Mode

Press "1" or ENTER key when VEHICLES TESTED appears on DRB
display. DRB shows vehicles supported by cartridge used. This screen
will be displayed for 5 seconds, then DRB menu will return. To return
to DRB menu sooner, press ATM key.

HOW TO USE Mode

Press "2" or DOWN arrow key to display HOW TO USE option.
Press ENTER key. DRB will display instructions for use of DRB with
cartridge being used.

CONFIGURE Mode
Press "3" key or ENTER key when CONFIGURE appears on DRB
display. Configure option allows technician to customize DRB display.
For example, if metric system is more useful, select METRIC from
appropriate menu. All selections made under CONFIGURE option remain
active until user changes selection.

SELECT SYSTEM Mode

This option lists all vehicle systems that can be tested
using DRB. To enter air bag diagnostics, press "6" or DOWN arrow key
to display PASSIVE REST option. Press ENTER key. DRB will display
PASSIVE REST menu. At PASSIVE REST menu, press "1" key (AIR BAG) or
press ENTER key. DRB will display AIR BAG MENU.

AIR BAG Menu

AIR BAG MENU displays all diagnostic modes available for
vehicle selected. Following AIR BAG MENU modes can be accessed: SYSTEM
TESTS, READ CODES (AIR BAG CODES), STATE DISPLAYS (AIR BAG STATE),
ACTUATOR TESTS, and ADJUSTMENTS (AIR BAG ADJUSTMENTS).

SYSTEM TESTS Mode

This mode is not available.

AIR BAG CODES Mode

This mode allows technician to read active and stored fault
codes stored in ACM memory. It also allows stored fault codes to be
erased. Follow DRB displays to erase fault codes.

AIR BAG STATE Displays Mode

Only option available at AIR BAG STATE displays mode is
MODULE INFO display. MODULE INFO display allows technician to read ACM
part number and application.

ACTUATOR TESTS Mode

This mode is not available.

AIR BAG ADJUSTMENTS

AIR BAGMode
RESTRAINT SYSTEM Article Text (p. 15)1996 Dodge Ram Van B2500For 1
 This mode is not available.

NOTE: Because DRB is grounded through engine ACM data

link connector, only one volt/ohm meter test lead
is required when using volt/ohm meter option. DRB
volt/ohm meter should only be used when diagnostic
charts require use of this option.

DRB Volt/Ohm Meter Mode

1) To access volt/ohm meter mode of DRB, connect Red volt/ohm
meter test lead to Red port, located on right top side of DRB.
2) To access volt meter, press VOLT/OHM key once. DRB is now
in volt meter mode. Touch test probe to connector or wire to be
measured. Read voltage on DRB display. When voltage testing is
complete, press VOLT/OHM key 3 times to exit volt meter mode.
3) To access ohm meter, press VOLT/OHM key twice. DRB is now
in ohm meter mode. Touch test probe to connector or wire to be
measured. Read resistance to circuit ground on DRB display. When
resistance testing is complete, press VOLT/OHM key twice to exit ohm
meter mode.

DRB ERROR MESSAGES

RAM TEST FAILURE Message

Power up DRB again with fingers off keypad. If error message
returns, replace DRB.

CARTRIDGE ERROR Message

Power up DRB again with fingers off keypad. If error message
returns, replace DRB cartridge.

KEY PAD TEST FAILURE Message

Power up DRB again with fingers off keypad. If error message
returns, replace DRB.

HIGH OR LOW BATTERY Message

Check battery voltage. If voltage is 11.7-13.0 volts, replace
DRB. If battery voltage is low, correct condition of vehicle battery
and reconnect DRB.

DIAGNOSTIC FAULT CODES (MESSAGES)

If any of following ACM diagnostic fault codes appear,

replace ACM.

* INTERNAL DIAGNOSTIC #1
* INTERNAL DIAGNOSTIC #2
* INTERNAL DIAGNOSTIC #3
* AECM ACCELEROMETER
* AECM OUTPUT
* AECM STORED ENERGY
* INCORRECT AECM AIR BAG RESTRAINT SYSTEM Article Text (p. 16)1996 Dodge Ram Van B250
 If any of the following ACM diagnostic fault codes appear,
perform required test procedure under DIAGNOSTIC TESTS,
starting with TEST 1A - TESTING SYSTEM FUNCTION.

* DRIVER SQUIB CIRCUIT OPEN

* DRIVER SQUIB CIRCUIT SHORTED
* DRIVER SQUIB TERM SHORTED TO BATTERY
* DRIVER SQUIB SHORTED TO GROUND
* LOSS OF IGNITION RUN ONLY
* LOSS OF IGNITION RUN/START
* PRETENSIONER CIRCUIT OPEN
* PRETENSIONER CIRCUIT SHORTED
* PRETENSIONER CIRCUIT SHORTED TO BATTERY
* PRETENSIONER CIRCUIT SHORTED TO GROUND
* WARNING LAMP CIRCUIT OPEN
* WARNING LAMP CIRCUIT SHORTED

DIAGNOSTIC TESTS

* PLEASE READ THIS FIRST *

Fig. 5: Restraint System Connector Identification

Courtesy of Chrysler Corp.

AIR BAG RESTRAINT SYSTEM Article Text (p. 17)1996 Dodge Ram Van B2500For 1
Fig. 6: Fuse Block Identification
Courtesy of Chrysler Corp. Copyright © 1998 Mitchell Repair In
AIR BAG RESTRAINT SYSTEM Article Text (p. 18)1996 Dodge Ram Van B2500For 1
TEST 1A - TESTING SYSTEM FUNCTION
 Ensure battery is fully charged. Connect DRB to data link
connector and turn ignition on. With DRB, select PASSIVE RESTRAINTS,
AIRBAG. Read both active and stored codes and record them. If there
are no active codes, erase stored codes.

TEST 2A - DRIVER SQUIB CIRCUIT OPEN

WARNING:Disconnect battery and wait 2 minutes before proceeding.

1) Disconnect driver-side air bag module. Connect jumper

between driver air bag line 1 and 2. Turn ignition on, then reconnect
battery. Use DRB to read active codes. If DRB shows DRIVER SQUIB
CIRCUIT SHORTED, replace driver side air bag module. If DRB does not
show DRIVER SQUIB SHORTED, disconnect clockspring 2-way connector.
2) Connect jumper between driver-side air bag line 1 and 2.
Use DRB to read active codes. If DRB shows DRIVER SQUIB CIRCUIT
SHORTED, replace clockspring. If DRB does not show DRIVER SQUIB
CIRCUIT SHORTED, disconnect battery and wait 2 minutes before
proceeding.
3) Remove jumper. Disconnect air bag control module 4-way
connector. Use an ohmmeter to test driver air bag line 1 circuit for
resistance between ACM 4-way connector and clockspring 2-way
connector. If resistance is above 1.0 ohms, repair open or high
resistance in driver-side air bag line 1 circuit.
4) If resistance is below 1.0 ohms, test driver air bag line
2 circuit for resistance between ACM 4-way connector and clockspring
2-way connector. If resistance is above 1.0 ohms, repair open or high
resistance in driver-side air bag line 2 circuit. If resistance is
below 1.0 ohms, replace air bag control module (ACM).

TEST 3A - DRIVER SQUIB CIRCUIT SHORTED

WARNING:Disconnect battery and wait 2 minutes before proceeding.

1) Disconnect driver-side air bag module. Turn ignition on,

then reconnect battery. Use DRB to read active codes. If DRB shows
DRIVER SQUIB CIRCUIT OPEN, replace driver-side air bag module. If DRB
does not show DRIVER SQUIB CIRCUIT OPEN, disconnect clockspring 2-way
connector. Use DRB to read active codes. If DRB shows DRIVER SQUIB
CIRCUIT OPEN, replace clockspring. If DRB does not show DRIVER SQUIB
CIRCUIT OPEN, disconnect battery and wait 2 minutes before proceeding.
2) Disconnect air bag control module 4-way connector. Turn
ignition on, then reconnect battery. Use DRB to read active codes. If
DRB shows DRIVER SQUIB CIRCUIT OPEN, repair driver-side air bag line 1
short to driver-side air bag line 2. If DRB does not show DRIVER SQUIB
CIRCUIT OPEN, replace air bag control module (ACM).

TEST 4A - DRIVER SQUIB TERM SHORTED TO BATTERY

WARNING:Disconnect battery and wait 2 minutes before proceeding.

1) Disconnect air bag control module 4-way connector.

AIR BAG RESTRAINT SYSTEM Article Text (p. 19)1996 Dodge Ram Van B2500For 1 Copyright © 1998 Mitchell Repair In
Disconnect driver-side air bag module. Turn ignition on, engine off.
Use DRB in voltmeter mode to probe driver-side air bag line 1 and 2.
If voltage is below 0.5 volts on either circuit, replace air bag
control module (ACM).
2) If voltage is above 0.5 volts, disconnect clockspring 2-
way connector. Use DRB in voltmeter mode to probe driver-side air bag
line 1 and 2. If voltage is below 0.5 volts, replace clockspring. If
voltage is above 0.5 volts, repair driver-side air bag line 1 or line
2 short to voltage.

TEST 5A - DRIVER SQUIB TERM SHORTED TO GROUND

WARNING:Disconnect battery and wait 2 minutes before proceeding.

1) Disconnect driver-side air bag module. Turn ignition on,

then reconnect battery. Use DRB to read active codes. If DRB does not
show DRIVER SQUIB TERM SHORTED TO GROUND, replace driver-side air bag
module. If DRB shows DRIVER SQUIB TERM SHORTED TO GROUND, disconnect
clockspring 2-way connector.
2) Use DRB to read active codes. If DRB does not show DRIVER
SQUIB TERM SHORTED TO GROUND, replace clockspring. If DRB shows DRIVER
SQUIB TERM SHORTED TO GROUND, disconnect battery and wait 2 minutes
before proceeding.
3) Disconnect air bag control module (ACM) 4-way connector.
Turn ignition on, then reconnect battery. Turn ignition off. Use DRB
in ohmmeter mode to probe driver-side air bag line 1 and line 2. If
resistance is below 5.0 ohms, repair driver-side air bag line 1 or
line 2 for a short to ground. If resistance is above 5.0 ohms, replace
air bag control module (ACM).

TEST 6A - LOSS OF IGNITION RUN ONLY

1) Remove and inspect fuse #1. If fuse is open, go to step

3). If fuse is okay, use DRB in voltmeter mode to probe IGN SW OUTPUT
CKT at fuse #1. If voltage is not above 10.0 volts, repair open
ignition switch output circuit. If voltage is above 10.0 volts,
reinstall fuse #1. Disconnect battery and wait 2 minutes before
proceeding.
2) Disconnect air bag control module 13-way connector. Turn
ignition on, then reconnect battery. Use DRB in voltmeter mode to
probe fused IGN SW OUTPUT RUN (CAV 2). If voltage is above 10.0 volts,
replace air bag control module (ACM). If voltage is below 10.0 volts,
repair open fused ignition switch output run circuit.
3) Turn ignition off. Use DRB in ohmmeter mode to probe fused
IGN SW OUTPUT RUN CKT. If resistance is above 5.0 ohms, replace fuse.
If resistance below 5.0 ohms, disconnect battery and wait 2 minutes
before proceeding.
4) Disconnect air bag control module 13-way connector. Turn
ignition on, then reconnect battery. Use DRB in ohmmeter mode to probe
fused ignition switch output run circuit (CAV 2). If resistance is
below 5.0 ohms, repair fused ignition switch output CKT for a short to
ground. If resistance is above 5.0 ohms, replace fuse and replace air RESTRAINT SYSTEM Article Text (p. 20)
AIR BAG
bag control module (ACM).

TEST 7A - LOSS OF IGNITION RUN/START

1) Remove and inspect fuse #18. If fuse is open, go to step

3). If fuse is okay, use DRB in voltmeter mode to probe IGN SW OUTPUT
CKT at fuse #18. If voltage is below 10.0 volts, repair open ignition
switch output circuit. If voltage is above 10.0 volts, reinstall fuse
#18. Disconnect battery and wait 2 minutes before proceeding.
2) Disconnect air bag control module 13-way connector. Turn
ignition on, then reconnect battery. Use DRB in voltmeter mode to
probe fused ignition switch output run/start circuit (CAV 1). If
voltage is above 10.0 volts, replace air bag control module (ACM). If
voltage is below 10.0 volts, repair open fused ignition switch output
run/start circuit.
3) Turn ignition off. Use DRB in ohmmeter mode to probe fused
ignition switch output circuit at fuse #18. If resistance is above 5.0
ohms, replace fuse. If resistance is below 5.0 ohms, disconnect
battery and wait 2 minutes before proceeding.
4) Disconnect air bag control module 13-way connector. Turn
ignition on, then reconnect battery. Use DRB in ohmmeter mode to probe
fused ignition switch output run/start circuit (CAV 1). If resistance
is below 5.0 ohms, repair fused ignition switch output run/start
circuit for a short to ground. Replace fuse. If resistance is above 5.
0 ohms, replace fuse. Replace air bag control module (ACM).

TEST 8A - SEAT BELT PRETENSIONER CIRCUIT OPEN

WARNING:Disconnect battery and wait 2 minutes before proceeding.

1) Disconnect pretensioner connector. Connect jumper between

cavity 1 and 2 of pretensioner connector. Turn ignition on and
reconnect battery. Use DRB to read active codes. If DRB shows SEAT
BELT PRETENSIONER CIRCUIT SHORTED, replace seat belt pretensioner
module. If DRB does not show SEAT BELT PRETENSIONER CIRCUIT SHORTED,
disconnect battery and wait 2 minutes before proceeding.
2) Disconnect air bag control module 4-way connector. Use an
ohmmeter to test seat belt pretensioner signal circuit for resistance
between pretensioner connector and air bag control module (ACM) 4-way
connector. If resistance is above 1.0 ohms, repair open or high
resistance in seat belt pretensioner signal circuit.
3) If resistance is below 1.0 ohms, test seat belt
pretensioner return circuit for resistance between pretensioner
connector and air bag control module (ACM) 4-way connector. If
resistance is above 1.0 ohms, repair open or high resistance in seat
pretensioner return circuit. If resistance is below 1.0 ohms, replace
air bag control module (ACM).

TEST 9A - SEAT BELT PRETENSIONER CIRCUIT SHORTED

WARNING:Disconnect battery and wait 2 minutes before proceeding.

AIR BAG RESTRAINT SYSTEM Article Text (p. 2
 1) Disconnect pretensioner connector. Turn ignition on, then
reconnect battery. Use DRB to read active codes. If DRB shows SEAT
BELT PRETENSIONER CIRCUIT OPEN, replace pretensioner module. If DRB
does not show SEAT BELT PRETENSIONER CIRCUIT OPEN, disconnect battery
and wait 2 minutes before proceeding.
2) Disconnect air bag control module (ACM) 4-way connector.
Turn ignition on, then reconnect battery. Use DRB to read active
codes. If DRB shows SEAT BELT PRETENSIONER CIRCUIT OPEN, repair seat
belt pretensioner return circuit short to signal circuit. If DRB does
not show SEAT BELT PRETENSIONER CIRCUIT OPEN, replace air bag control
module (ACM).

TEST 10A - SEAT BELT PRETENSIONER CIRCUIT SHORTED TO BATTERY

WARNING:Disconnect battery and wait 2 minutes before proceeding.

1) Disconnect air bag control module 4-way connector.

Disconnect pretensioner module connector. Turn ignition on, engine
off. Use DRB in voltmeter mode to probe pretensioner return or signal
circuits.
2) If voltage is above 0.5 volts, repair seat belt
pretensioner return or signal circuits shorted to voltage. If voltage
is below 0.5 volts, replace air bag control module (ACM).
\

TEST 11A - SEAT BELT PRETENSIONER CIRCUIT SHORTED TO GROUND

WARNING:Disconnect battery and wait 2 minutes before proceeding.

1) Disconnect pretensioner module connector. Turn ignition

on, then reconnect battery. Use DRB to read active codes. If DRB does
not show SEAT BELT PRETENSIONER CKT SHORTED TO GROUND, replace
pretensioner module. If DRB shows SEAT BELT PRETENSIONER CKT SHORTED
TO GROUND, disconnect battery and wait 2 minutes before proceeding.
2) Disconnect air bag control module 4-way connector. Turn
ignition on, then reconnect battery. Use DRB to read active codes. If
DRB does not show SEAT BELT PRETENSIONER CKT SHORTED TO GROUND, repair
seat belt pretensioner return or signal circuit for short to ground.
If DRB shows SEAT BELT PRETENSIONER CKT SHORTED TO GROUND, replace air
bag control module (ACM).

TEST 12A - WARNING LAMP OPEN/SHORTED

1) Disconnect message center connector. Remove and inspect

warning lamp bulb. If bulb is no good, replace bulb. If bulb is okay,
inspect circuit board. If circuit board is no good, replace circuit
board. If circuit board is okay, turn ignition on, engine off.
2) Use DRB in voltmeter mode to probe air bag warning lamp
driver CKT. If voltage is above 1.0 volts, repair air bag warning lamp
driver for short to voltage. If voltage is below 1.0 volts, use
voltmeter to probe fused IGN SW OUTPUT CKT. If voltage is below 10.0
volts,BAG
AIR repairRESTRAINT
open fused ignition
SYSTEMswitchArticle
output circuit.
Text (p.If voltage
22)1996is Dodge Ram Van B2500For 1 Copyright © 1998 Mitchell Repair In
above 10.0 volts, turn ignition off.
3) Use DRB in ohmmeter mode to probe air bag warning driver
circuit. If resistance is below 5.0 ohms, repair air bag warning lamp
driver circuit for short to ground. If resistance is above 5.0 ohms,
disconnect battery and wait 2 minutes before proceeding.
4) Disconnect air bag control module 13-way connector. Use
ohmmeter to test resistance of warning lamp driver circuit between ACM
connector (CAV7) and message center connector (CAV 8). If resistance
is above 5.0 ohms, repair open air bag warning lamp driver circuit. If
resistance is below 5.0 ohms, replace air bag control module (ACM).

WIRING DIAGRAMS

Fig. 7: SRS Wiring Diagram (Ram Van/Wagon)

AIR BAG RESTRAINT SYSTEM Article Text (p. 23)
END OF ARTICLE

AIR BAG RESTRAINT SYSTEM Article Text (p. 24)1996 Dodge Ram Van B2500For 1 Copyright © 1998 Mitchell Repair In