Lost Communication with Front Airbag Sensor LH - Airbag System (except TMC Made)

SUPPLEMENTAL RESTRAINT SYSTEM: AIRBAG SYSTEM (except TMC Made): B1617/84,B1618/84: Lost Communication with Front Airbag Sensor LH
B1618/84 - Front Airbag Sensor LH Initialization Incomplete

DESCRIPTION

The front airbag sensor LH circuit consists of the center airbag sensor assembly and front airbag sensor LH.

The front airbag sensor LH detects impacts to the vehicle and sends signals to the center airbag sensor assembly to determine if the airbag should be deployed.

These DTCs are stored when a malfunction is detected in the front airbag sensor LH circuit.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK CONNECTORS

(a) Turn the ignition switch off.

(b) Disconnect the cable from the negative (-) battery terminal.

CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(c) Check that the connectors are properly connected to the center airbag sensor assembly and front airbag sensor LH. Also check that the connectors that link the engine room main wire and instrument panel wire are properly connected.

OK:

The connectors are properly connected.

HINT
If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.

(d) Disconnect the connectors from the center airbag sensor assembly and front airbag sensor LH. Also disconnect the connectors that link the engine room main wire and instrument panel wire.

(e) Check that the terminals of connectors are not damaged.

OK:

The terminals are not deformed or damaged.

NG -- REPLACE WIRE HARNESS
OK -- Continue to next step.

2. CHECK FRONT AIRBAG SENSOR LH CIRCUIT (OPEN)

(a) Connect the connectors that link the engine room main wire and instrument panel wire.





(b) Using SST, connect terminals 30 (+SL) and 28 (-SL) of connector B.

NOTICE:
Do not forcibly insert SST into the terminals of the connector when connecting.

SST : 09843-18040

(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.

3. CHECK FRONT AIRBAG SENSOR LH CIRCUIT (SHORT)

(a) Disconnect SST from connector B.





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

Standard Resistance:





NG -- CHECK INSTRUMENT PANEL WIRE (SHORT)
OK -- Continue to next step.

4. CHECK FRONT AIRBAG SENSOR LH CIRCUIT (SHORT TO B+)

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





(b) Turn the ignition switch on (IG).

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

Standard Voltage:





NG -- CHECK INSTRUMENT PANEL WIRE (SHORT TO B+)
OK -- Continue to next step.

5. CHECK FRONT AIRBAG SENSOR LH CIRCUIT (SHORT TO GROUND)

(a) Turn the ignition switch off.





(b) Disconnect the cable from the negative (-) battery terminal.

CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

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

Standard Resistance:





NG -- CHECK INSTRUMENT PANEL WIRE (SHORT TO GROUND)
OK -- Continue to next step.

6. CHECK FRONT AIRBAG SENSOR LH

(a) Connect the connector to the center airbag sensor assembly.





(b) Interchange the front airbag sensor RH with LH and connect the connectors.

(c) Connect the cable to the negative (-) battery terminal.

(d) Turn the ignition switch on (IG), and wait for at least 60 seconds.

(e) Clear the DTCs stored in the memory Airbag System (except TMC Made).

(f) Turn the ignition switch off.

(g) Turn the ignition switch on (IG), and wait for at least 60 seconds.

(h) Check for DTCs Airbag System (except TMC Made).

Result:





HINT
Codes other than DTCs B1612/83, B1613/83, B1617/84 and B1618/84 may be output at this time, but they are not related to this check.

C -- REPLACE FRONT AIRBAG SENSOR LH Removal

B -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal

A -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting

7. CHECK INSTRUMENT PANEL WIRE (OPEN)

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





HINT
SST has already been inserted into connector B.

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

Standard Resistance:





NG -- REPLACE INSTRUMENT PANEL WIRE

OK -- REPLACE ENGINE ROOM MAIN WIRE

8. CHECK INSTRUMENT PANEL WIRE (SHORT)

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





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

Standard Resistance:





NG -- REPLACE INSTRUMENT PANEL WIRE

OK -- REPLACE ENGINE ROOM MAIN WIRE

9. CHECK INSTRUMENT PANEL WIRE (SHORT TO B+)

(a) Turn the ignition switch off.





(b) Disconnect the cable from the negative (-) battery terminal.

CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(c) Disconnect the instrument panel wire connector from the engine room main wire.

(d) Connect the cable to the negative (-) battery terminal.

(e) Turn the ignition switch on (IG).

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

Standard Voltage:





NG -- REPLACE INSTRUMENT PANEL WIRE

OK -- REPLACE ENGINE ROOM MAIN WIRE

10. CHECK INSTRUMENT PANEL WIRE (SHORT TO GROUND)

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





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

Standard Resistance:





NG -- REPLACE INSTRUMENT PANEL WIRE

OK -- REPLACE ENGINE ROOM MAIN WIRE