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SUPPLEMENTAL RESTRAINT SYSTEMS AIRBAG SYSTEM(for Type A) B1612 Front Airbag Sensor Lost
Communication (RH) B1613 Front Airbag Sensor Initialization Error (RH)

DESCRIPTION

The front airbag sensor RH circuit consists of the airbag ECU assembly and front airbag sensor RH.
The front airbag sensor RH detects impacts to the vehicle and sends signals to the airbag ECU assembly to determine if the
airbag should be deployed.
DTC B1612 or B1613 is stored when a malfunction is detected in the front airbag sensor RH circuit.
DTC No. Detection Item DTC Detection Condition Trouble Area
One of the following ·
conditions is met: ·
· The airbag ECU
assembly detects a ·
line short circuit
signal, open circuit ·
Instrument panel wire
signal, short circuit to
Engine room main
ground signal or short
Front Airbag Sensor Lost wire
B1612 circuit to B+ signal in
Communication (RH) Front airbag sensor
the front airbag
RH
sensor RH circuit for 2
Airbag ECU assembly
seconds.
· A front airbag sensor
RH malfunction.
· An airbag ECU
assembly
malfunction.

One of the following ·

conditions is met: ·
· The airbag ECU
assembly detects a ·
line short circuit
signal, open circuit ·
Instrument panel wire
signal, short circuit to
Engine room main
ground signal or short
Front Airbag Sensor wire
B1613 circuit to B+ signal in
Initialization Error (RH) Front airbag sensor
the front airbag
RH
sensor RH circuit for 2
Airbag ECU assembly
seconds.
· A front airbag sensor
RH malfunction.
· An airbag ECU
assembly
malfunction.

WIRING DIAGRAM

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CAUTION / NOTICE / HINT

NOTICE:
· After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-)
battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal
notices before proceeding with work.
Click hereGeneral>INTRODUCTION>REPAIR INSTRUCTION>PRECAUTION
· When disconnecting and reconnecting the battery
HINT:
When disconnecting and reconnecting the battery, there is an automatic learning function that completes learning
when the respective system is used.
Click hereGeneral>SETUP>WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL>AUTOMATIC LEARNING
CHART

PROCEDURE

1.CHECK CONNECTION OF CONNECTORS

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 airbag ECU assembly and front airbag sensor RH.

Result:
Proceed to
The connectors are properly connected
The connectors are not properly connected

The connectors are properly connected

2.CHECK CONNECTORS

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The connectors are not properly connected

CONNECT CONNECTORS PROPERLY

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2.CHECK CONNECTORS

a. Disconnect the connectors from the airbag ECU assembly and front airbag sensor RH.

b.

*1 Front Airbag Sensor RH

*2 Airbag ECU Assembly
*3 Engine Room Main Wire
*4 Instrument Panel Wire

Check that the connectors (on the airbag ECU assembly side and front airbag sensor RH side) are not damaged.

Result:
Proceed to
The connectors are not deformed or damaged
The connectors are deformed or damaged

The connectors are not deformed or damaged

3.CHECK FRONT AIRBAG SENSOR RH CIRCUIT

The connectors are deformed or damaged

REPLACE ENGINE ROOM MAIN WIRE OR INSTRUMENT PANEL WIRE

3.CHECK FRONT AIRBAG SENSOR RH CIRCUIT

a. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

*1 Front Airbag Sensor RH *2 Airbag ECU Assembly

*3 Connector E *4 Connector B
*5 Service Wire - -
Front view of wire harness connector Rear view of wire harness connector
*a *b
(to Front Airbag Sensor RH) (to Airbag ECU Assembly)

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b. Turn the ignition switch to ON.

c. Measure the voltage according to the value(s) in the table below.

Standard Voltage:
Tester Switch Specified
Connection Condition Condition
A10-2 (+SR) - Ignition switch
Below 1 V
Body ground ON
A10-1 (-SR) - Ignition switch
Below 1 V
Body ground ON

d. Turn the ignition switch off.

e. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

f. Using a service wire, connect terminals 29 (+SR) and 27 (-SR) of connector B.

NOTICE:
Do not forcibly insert the service wire into the terminals of the connector when connecting a service wire.

g. Measure the resistance according to the value(s) in the table below.

Standard Resistance:
Tester Specified
Condition
Connection Condition
A10-2 (+SR) -
Always Below 1 Ω
A10-1 (-SR)

h. Disconnect the service wire from connector B.

i. Measure the resistance according to the value(s) in the table below.

Standard Resistance:
Tester Specified
Condition
Connection Condition
A10-2 (+SR) -
Always 1 MΩ or higher
A10-1 (-SR)
A10-2 (+SR) -
Always 1 MΩ or higher
Body ground
A10-1 (-SR) -
Always 1 MΩ or higher
Body ground

Result:
Proceed to
OK
NG

OK

4.CHECK FRONT AIRBAG SENSOR RH

NG

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5.CHECK INSTRUMENT PANEL WIRE

4.CHECK FRONT AIRBAG SENSOR RH

a.

*1 Front Airbag Sensor LH

*2 Airbag ECU Assembly

Connect the connectors to the airbag ECU assembly.

b. Interchange the front airbag sensor RH with LH and connect the connectors to them.

c. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

d. Turn the ignition switch to ON, and wait for at least 60 seconds.

e. Clear the DTCs stored in memory.

Click hereVehicle Interior>SUPPLEMENTAL RESTRAINT SYSTEMS>AIRBAG SYSTEM (for Type A)>DTC CHECK / CLEAR
Body Electrical > SRS Airbag > Clear DTCs

Execute

f. Turn the ignition switch off.

g. Turn the ignition switch to ON, and wait for at least 60 seconds.

h. Check for DTCs.

Click hereVehicle Interior>SUPPLEMENTAL RESTRAINT SYSTEMS>AIRBAG SYSTEM (for Type A)>DTC CHECK / CLEAR
Body Electrical > SRS Airbag > Trouble Codes

Execute

Result:
Proceed to
DTC B1612 or B1613 is output
DTC B1617 or B1618 is output
DTC B1612, B1613, B1617 and B1618 are not output

HINT:
Codes other than DTC B1612, B1613, B1617 and B1618 may be output at this time, but they are not related to this
check.

i. Turn the ignition switch off.

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j. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

k. Return the front airbag sensor LH and RH to their original positions and connect the connectors to them.

DTC B1612 or B1613 is output

REPLACE AIRBAG ECU ASSEMBLY

Click hereVehicle Interior>SUPPLEMENTAL RESTRAINT SYSTEMS>CENTER AIRBAG SENSOR

ASSEMBLY>REMOVAL

DTC B1617 or B1618 is output

REPLACE FRONT AIRBAG SENSOR RH

Click hereVehicle Interior>SUPPLEMENTAL RESTRAINT SYSTEMS>FRONT AIRBAG SENSOR>REMOVAL

DTC B1612, B1613, B1617 and B1618 are not output

USE SIMULATION METHOD TO CHECK

Click hereVehicle Interior>SUPPLEMENTAL RESTRAINT SYSTEMS>AIRBAG SYSTEM (for Type A)>DIAGNOSIS

SYSTEM

5.CHECK INSTRUMENT PANEL WIRE

a. Disconnect the instrument panel wire connector from the engine room main wire.

*1 Front Airbag Sensor RH *2 Airbag ECU Assembly

*3 Engine Room Main Wire *4 Instrument Panel Wire
*5 Connector C *6 Connector B
*7 Service Wire - -
Front view of wire harness connector Rear view of wire harness connector
*a *b
(to Engine Room Main Wire) (to Airbag ECU Assembly)

b. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

c. Turn the ignition switch to ON.

d. Measure the voltage according to the value(s) in the table below.

Standard Voltage:
Tester Switch Specified
Connection Condition Condition
AG4-1 (-SR) - Ignition switch
Below 1 V
Body ground ON
AG4-2 (+SR) - Ignition switch
Below 1 V
Body ground ON

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e. Turn the ignition switch off.

f. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

g. Using a service wire, connect terminals 29 (+SR) and 27 (-SR) of connector B.

NOTICE:
Do not forcibly insert the service wire into the terminals of the connector when connecting a service wire.

h. Measure the resistance according to the value(s) in the table below.

Standard Resistance:
Tester Specified
Condition
Connection Condition
AG4-1 (-SR) -
Always Below 1 Ω
AG4-2 (+SR)

i. Disconnect the service wire from connector B.

j. Measure the resistance according to the value(s) in the table below.

Standard Resistance:
Tester Specified
Condition
Connection Condition
AG4-1 (-SR) -
Always 1 MΩ or higher
AG4-2 (+SR)
AG4-1 (-SR) -
Always 1 MΩ or higher
Body ground
AG4-2 (+SR) -
Always 1 MΩ or higher
Body ground

Result:
Proceed to
OK
NG

OK

REPLACE ENGINE ROOM MAIN WIRE

NG

REPLACE INSTRUMENT PANEL WIRE

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