Test Notes

Normal Operation
The air bag diagnostic monitor measures the resistance between Pin 21 (Circuit 620, P/LB) and Pin 3 (air bag diagnostic monitor reference ground). If the air bag diagnostic monitor measures a difference of more than 2.0 ohms between Pin 21 and Pin 3, it will flash out code 45.

Note that Circuit 620 (P/LB) is grounded to the side of the LH front air bag sensor case and the case is grounded to the vehicle at its mounting point.

Possible Causes
High resistance on Pin 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 front air bag sensor mounting location.
2. An open or damaged wire in Circuit 620 (P/LB) from Pin 21 of the air bag diagnostic monitor harness connector to LH front air bag sensor and bracket.
3. An open circuit inside LH front air bag sensor.