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Test Notes

NORMAL OPERATION
The air bag diagnostic monitor measures the resistance between Pin C277-16, Circuit 613 (DB/W) and Pin C277-3, Circuit 57 (BK), ground. If the air bag diagnostic monitor measures a difference of more than 2.0 ohms between Pin C277-16 and Pin C277-3, it will flash Diagnostic Trouble code (DTC) 21 on the air bag indicator.

It is important to note that Circuit 613 (DB/W) is grounded to the side of the safing sensor case, and the case of the safing sensor is grounded to the vehicle in the LH cowl panel. A good ground connection, at both the case and the vehicle body, is important to proper circuit operation.

POSSIBLE CAUSES
High resistance at Pin C277-16, Circuit 613 (DB/W) to ground can be caused by:
1. A poor connection due to loose mounting or dirt at the LH cowl panel safing sensor mounting surface.
2. An open or damaged wire in Circuit 613 (DB/W) from Pin C277-16 of the air bag diagnostic monitor connector to the LH cowl panel safing sensor.
3. An open circuit inside the LH cowl panel safing sensor.