RS–136 SUPPLEMENTAL RESTRAINT SYSTEM – AIRBAG SYSTEM

DTC B1650/32 Occupant Classification System Malfunction

DESCRIPTION
The occupant classification system circuit consists of the center airbag sensor and the occupant
classification system.
When the center airbag sensor receives signals from the occupant classification ECU, it determines
whether or not the front passenger airbag, front seat side airbag RH and seat belt pretensioner RH should
be operated.
DTC B1650/32 is set when a malfunction is detected in the occupant classification system circuit.
DTC No. DTC Detection Condition Trouble Area
B1650/32 When one of following conditions is met: • Floor wire
• Occupant classification system • Occupant classification system
malfunction • Center airbag sensor
• Center airbag sensor detects line short
signal, open signal, short to ground signal
or short to B+ signal in occupant
classification system circuit for 2 seconds
• Center airbag sensor malfunction

WIRING DIAGRAM

Occupant Classification ECU Center Airbag Sensor

FSR+ FSP+

RS

FSR- FSP-

H102167E01
 SUPPLEMENTAL RESTRAINT SYSTEM – AIRBAG SYSTEM RS–137

INSPECTION PROCEDURE

1 CHECK FOR DTC (CENTER AIRBAG SENSOR)

(a) Turn the ignition switch ON, and wait for at least 60
seconds.
(b) Clear the DTCs (see page RS-49).
(c) Turn the ignition switch OFF.
(d) Turn the ignition switch ON, and wait for at least 60
seconds.
Center Airbag Sensor (e) Check for DTCs (see page RS-49).
Occupant
Classification OK:
ECU DTC B1650/32 is not output.
HINT:
DTCs other than B1650/32 may be output at this time,
but they are not related to this check.
DTC 32 OK USE SIMULATION METHOD TO CHECK
DLC3

CG TC

H100887E04

NG

2 CHECK FOR DTC (OCCUPANT CLASSIFICATION ECU)

(a) Turn the ignition switch ON, and wait for at least 10
seconds. RS
(b) Using the intelligent tester (with CAN VIM), check for
DTCs of the occupant classification ECU (see page RS-
249).
OK:
DTC is not output.
NG GO TO DTC CHART

OK

3 CHECK CONNECTION OF CONNECTOR

(a) Turn the ignition switch OFF.

(b) Disconnect the cable from the negative (-) battery
terminal, and wait for at least 90 seconds.
(c) Check that the connectors are properly connected to the
center airbag sensor and the occupant classification
ECU.
OK:
The connectors are properly connected.
 RS–138 SUPPLEMENTAL RESTRAINT SYSTEM – AIRBAG SYSTEM

NG CONNECT CONNECTOR

OK

4 CHECK FLOOR WIRE (OPEN)

(a) Disconnect the connectors from the center airbag sensor

and occupant classification ECU.
(b) Using a service wire, connect L1-8 (FSR+) and L1-4
(FSR-) of connector C.
C B NOTICE:
D A Do not forcibly insert the service wire into the
Center Airbag Sensor terminals of the connector when connecting.
Occupant (c) Measure the resistance of the wire harness side
Classification connector.
ECU Standard resistance:
Connector B
w/ Curtain shield airbag
w/ Curtain Shield Airbag
Tester Connection Specified Condition
L7 L7-16 (FSP+) - L7-24 (FSP-) Below 1 Ω

Connector C
w/o Curtain shield airbag
Tester Connection Specified Condition
L1 L6-12 (FSP+) - L6-13 (FSP-) Below 1 Ω
FSP+ FSP-

w/o Curtain Shield Airbag NG REPAIR OR REPLACE FLOOR WIRE

FSR+ FSR- L6
5 4 3 2 1

10 9 8 7 6

15 14 13 12 11

RS FSP- FSP+
C123582E03

OK
 SUPPLEMENTAL RESTRAINT SYSTEM – AIRBAG SYSTEM RS–139

5 CHECK FLOOR WIRE (SHORT)

(a) Disconnect the service wire from connector C.

(b) Measure the resistance of the wire harness side
connector.
Standard resistance:
C B w/ Curtain shield airbag
D A
Tester Connection Specified Condition
Center Airbag Sensor L7-16 (FSP+) - L7-24 (FSP-) 1 MΩ or higher
Occupant
Classification ECU w/o Curtain shield airbag
Tester Connection Specified Condition
Connector B
L6-12 (FSP+) - L6-13 (FSP-) 1 MΩ or higher
w/ Curtain w/o Curtain
Shield Airbag Shield Airbag NG REPAIR OR REPLACE FLOOR WIRE

L7 L6
5 4 3 2 1

10 9 8 7 6

15 14 13 12 11

FSP- FSP+
FSP+ FSP-
C123583E02

OK

6 CHECK FLOOR WIRE (TO B+)

(a) Connect the cable to the negative (-) battery terminal,

and wait for at least 2 seconds.
(b) Turn the ignition switch ON. RS
(c) Measure the voltage of the wire harness side connector.
C B Standard voltage:
D A w/ Curtain shield airbag
Center Airbag Sensor Tester Connection Specified Condition
Occupant
L7-16 (FSP+) - Body ground Below 1 V
Classification ECU
L7-24 (FSP-) - Body ground Below 1 V

Connector B w/o Curtain shield airbag

w/ Curtain w/o Curtain Tester Connection Specified Condition
Shield Airbag Shield Airbag L6-12 (FSP+) - Body ground Below 1 V
L6-13 (FSP-) - Body ground Below 1 V
L7 L6
5 4 3 2 1 NG REPAIR OR REPLACE FLOOR WIRE
10 9 8 7 6

15 14 13 12 11

FSP- FSP+
FSP+ FSP-
C123583E03

OK
 RS–140 SUPPLEMENTAL RESTRAINT SYSTEM – AIRBAG SYSTEM

7 CHECK FLOOR WIRE (TO GROUND)

(a) Turn the ignition switch OFF.

(b) Disconnect the cable from the negative (-) battery
terminal, and wait for at least 90 seconds.
(c) Measure the resistance of the wire harness side
C B connector.
D A Standard resistance:
Center Airbag Sensor w/ Curtain shield airbag
Occupant
Tester Connection Specified Condition
Classification ECU
L7-16 (FSP+) - Body ground 1 MΩ or higher
L7-24 (FSP-) - Body ground 1 MΩ or higher
Connector B

w/ Curtain w/o Curtain w/o Curtain shield airbag

Shield Airbag Shield Airbag Tester Connection Specified Condition
L6-12 (FSP+) - Body ground 1 MΩ or higher
L7 L6 L6-13 (FSP-) - Body ground 1 MΩ or higher
5 4 3 2 1

10 9 8 7 6

15 14 13 12 11
NG REPAIR OR REPLACE FLOOR WIRE

FSP- FSP+
FSP+ FSP-
C123583E04

OK

8 CHECK CENTER AIRBAG SENSOR ASSEMBLY

(a) Replace the center airbag sensor (see page RS-374).

HINT:
RS Perform the inspection using parts from a normal vehicle
when possible.
(b) Connect the connectors to the center airbag sensor.
(c) Connect the cable to the negative (-) battery terminal,
Center Airbag Sensor and wait for at least 2 seconds.
Occupant
Classification (d) Turn the ignition switch ON, and wait for at least 60
ECU seconds.
(e) Clear the DTCs (see page RS-49).
(f) Turn the ignition switch OFF.
(g) Turn the ignition switch ON, and wait for at least 60
seconds.
DTC 32
DLC3 (h) Check for DTCs (see page RS-49).
OK:
DTC B1650/32 is not output.
HINT:
DTCs other than B1650/32 may be output at this time,
CG TC but they are not related to this check.
OK USE SIMULATION METHOD TO CHECK
H100887E05

NG
 SUPPLEMENTAL RESTRAINT SYSTEM – AIRBAG SYSTEM RS–141

9 REPLACE OCCUPANT CLASSIFICATION ECU

(a) Turn the ignition switch OFF.

(b) Disconnect the cable from the negative (-) battery
terminal, and wait for at least 90 seconds.
(c) Replace the occupant classification ECU (see page RS-
392).
NEXT

10 PERFORM ZERO POINT CALIBRATION

(a) Connect the cable to the negative (-) battery terminal,

and wait for at least 2 seconds.
(b) Turn the ignition switch ON.
(c) Using the intelligent tester, perform the zero point
calibration (see page RS-241).
OK:
COMPLETED is displayed on the tester.
NEXT

11 PERFORM SENSITIVITY CHECK

(a) Using the intelligent tester, perform the sensitivity check

(see page RS-241).
Standard value:
27 to 33 kg (59.52 to 72.75 lb)
NEXT
RS
END