42: LH Primary Crash Sensor Feed/Return Circuit Open

DIAGNOSTIC TROUBLE CODE 42

LH Primary Crash Sensor Feed/Return Circuit Open

Normal Operation
The voltage at Pin 18 (Circuit 619, PK/W) is approximately 10 volts (±1 volt) and is pulsed low during this test. Circuit 619 (PK/W) is connected to Circuit 825 (Y/LG) inside LH primary crash sensor. Therefore, the voltage at Pin 6 should be the same as the voltage at Pin 18. If the voltage at Pin 6 is lower than the voltage at Pin 18 or it the voltage at Pin 6 does not pulse low during this test, the air bag diagnostic monitor will flash code 42.

Possible Causes
Code 42 can be caused by:
1. An open circuit in the wiring harness in either Circuit 619 (PK/W) or Circuit 625 (Y/LG).
2. An open circuit in LH primary crash sensor across the PK/W and Y/LG wires.
3. A short in the wiring harness between another wire and Circuits 619 (PK/W) or 625 (Y/LG) can prevent Pin 6 from pulsing low.

Electrical Schematic - Diagnostic Trouble Code 42:

Pinpoint Tests 42-1 - 42-3: