Test D: LFC 14/DTC B1901 - Front Crash Sensor Circuit Short to Gnd.

D1:

D2 - D3:

D3 - D4:

D5:

Normal Operation

CAUTION: The crash sensors are sensitive electronic devices. To avoid possible component damage, do not attempt to test crash sensors with an ohmmeter.

During normal operation the Restraints Control Module (RCM) monitors the resistance to ground of circuits 617 (PK/OG) and 618 (VT/LG). If there is a ground short (less than 10,000 ohms to ground), in the front crash sensor or its wiring path, the RCM will store Diagnostic Trouble Code (DTC) B1901 in memory. The RCM will also flash Lamp Fault Code (LFC) 14 (or higher priority code if one exists) on the air bag indicator.

Possible Causes
A front crash sensor shorted to ground fault can be caused by:
^ a short to ground on circuit 617 (PK/OG) or 618 (VT/LG).
^ a damaged or inoperative front crash sensor.
^ an RCM internal concern.