Test Notes

Normal Operation
The air bag diagnostic monitor measures the voltage at Pins C1-2, Circuit 624 (Y/W) and C1-6, Circuit 625 (Y/LG) of the air bag diagnostic monitor connector. The normal voltage at these pins is approximately 10 volts (± 1 volt) when the ignition switch is in RUN or B+ when the ignition switch is OFF. If the air bag diagnostic monitor detects that the voltage at Pins C1-2 or C1-6 has dropped to 5 volts or less, the air bag diagnostic monitor will flash DTC 14 on the air bag indicator to indicate a short to ground on any of these circuits (refer to Possible Causes for additional circuits that may be shorted to ground). When flashing DTC 14, the air bag diagnostic monitor blows its internal thermal fuse. This disables the air bag deployment circuit. If the voltage at Pins C1-2 and C1-6 returns to normal, a DTC 51 will be present due to the open thermal fuse.

NOTE: Diagnostic Trouble Code 14 will flash only while the short to ground is present.

Possible Causes
A drop in voltage at air bag diagnostic monitor Pins C1-2 and C1-6 can be caused by:

1. A short to ground within the wiring harness on Circuits 624 (Y/W), 625 (Y/LG), 617 (PK/O) or 619 (PK/W), causing the diagnostic voltage to drop.

2. An internal short to case ground within either of the primary crash sensors.

NOTE: The gray diagnostic monitor harness connector contains a shorting bar inside the connector that will short Pins C1-2 and C1-3 together whenever the air bag diagnostic monitor is disconnected. Since Pin C1-3 is ground, shorting Pin C1-2 to Pin C1-3 will cause a short to ground on both Pins C1-2 and C1-17. Make sure to remove the plastic locking wedge from the gray harness connector before checking resistance of these circuits to ground.