B1149

SUPPLEMENTAL RESTRAINT SYSTEM: AIRBAG SYSTEM: B1149/37: Front Airbag Sensor LH Circuit Malfunction

DTC B1149/37 - Front Airbag Sensor LH Circuit Malfunction

DESCRIPTION

The front airbag sensor LH circuit consists of the diagnosis circuit and the frontal deceleration sensor, etc.
If the center airbag sensor assembly receives signals from the frontal deceleration sensor, it judges whether or not the SRS should be activated.
DTC B1149/37 is recorded when a malfunction is detected in the front airbag sensor LH circuit.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK FRONT AIRBAG SENSOR LH




(a) Turn the ignition switch to the ON position, and wait for at least 60 seconds.
(b) Clear the DTCs stored in memory DTC Check / Clear.
(c) Turn the ignition switch to the LOCK position.
(d) Turn the ignition switch to the ON position, and wait for at least 60 seconds.
(e) Check the DTCs DTC Check / Clear.
OK:
DTC B1149/37 is not output.
HINT: Codes other than code B1149/37 may be output at this time, but they are not related to this check.

NG -- CHECK CONNECTION OF CONNECTORS
OK -- USE SIMULATION METHOD TO CHECK
2. CHECK CONNECTION OF CONNECTORS
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Check that the connectors are properly connected to the center airbag sensor assembly and the front airbag sensor LH.
OK:
The connectors are connected.
NG -- CONNECT CONNECTORS, THEN GO TO STEP1
OK -- Continue to next step.
3. CHECK FRONT AIRBAG SENSOR LH CIRCUIT (OPEN)




(a) Disconnect the connectors from the center airbag sensor assembly and the front airbag sensor LH.
(b) Using a service wire, connect A28-15 (+SL) and A28-26 (-SL) of connector "B".
NOTE:
Do not forcibly insert a service wire into the terminals of the connector when connecting.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- CHECK INSTRUMENT PANEL WIRE (OPEN)
OK -- Continue to next step.
4. CHECK FRONT AIRBAG SENSOR LH




(a) Disconnect the service wire from connector "B".
(b) Connect the connector to the center airbag sensor assembly.
(c) Interchange the side airbag sensor RH with LH and connect the connectors to them.
(d) Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
(e) Turn the ignition switch to the ON position, and wait for at least 60 seconds.
(f) Clear the DTCs stored in memory DTC Check / Clear.
(g) Turn the ignition switch to the LOCK position.
(h) Turn the ignition switch to the ON position, and wait for at least 60 seconds.
(i) Check the DTCs DTC Check / Clear.
Result:






NG:B -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY
NG:A -- REPLACE FRONT AIRBAG SENSOR LH
OK -- USE SIMULATION METHOD TO CHECK
5. CHECK INSTRUMENT PANEL WIRE (OPEN)




(a) Disconnect the instrument panel wire connector from the engine room main wire.
HINT: The service wire has already been inserted into connector "B".
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE INSTRUMENT PANEL WIRE
OK -- REPAIR OR REPLACE ENGINE ROOM MAIN WIRE