Test Notes

Normal Operation
Note that Circuit 620 (P/LB) is grounded to the side of the LH primary crash sensor case and the case is grounded to the vehicle at its mounting point.

The air bag diagnostic monitor measures the resistance between Pin C2-21, Circuit 620 (P/LB) and Pin C1-3, Circuit 649 (BK/O), diagnostic monitor reference ground. If the air bag diagnostic monitor measures a difference of more than 2.0 ohms between Pin C2-21 and Pin C1-3, it will flash DTC 45.

Possible Causes
High resistance on Pin C2-21, Circuit 620 (P/LB) to ground can be caused by:

1. A poor connection due to loose mounting, dirt or corrosion at the LH primary crash front air bag sensor and bracket mounting location.

2. An open or damaged wire (Circuit 620, P/LB) from Pin C2-21 of the air bag diagnostic monitor harness connector to LH primary crash sensor.

3. An open circuit inside LH primary crash sensor.