hey, uh, wasn't this thread talking about something else?
DIAGNOSTIC TROUBLE CODE 21
Safing Sensor Not Mounted to Vehicle Properly
Normal Operation
The air bag diagnostic monitor measures the resistance between Pin 16 (Circuit 613, DB/W) and Pin 3 (Circuit 57, BK ground). If the air bag diagnostic monitor measures a difference of more than 2.0 ohms between Pin 16 and Pin 3, it will flash out code 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 kick 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 16 (Circuit 613, DB/W) to ground can be caused by:
16. A poor connection due to loose mounting or dirt at the LH kick panel safing sensor mounting surface.
17. An open or damaged wire in Circuit 613 (DB/W) from Pin 16 of the air bag diagnostic monitor connector to the LH kick panel safing sensor.
18. An open circuit inside the LH kick panel safing sensor.
I don't really think you have a 12, which is:
DIAGNOSTIC TROUBLE CODE 12
Low Battery Voltage
Normal Operation
The air bag diagnostic monitor measures the voltage at Pin 13 of the air bag diagnostic monitor connector. Voltage at Pin 13 should be equal to battery voltage. If the voltage measured at Pin 13 drops to less than 9 volts, the diagnostic monitor will flash out code 12.
Possible Causes
Low battery voltage at diagnostic monitor Pin 13 can be caused by:
NOTE:
If fuse 7 is blown, make sure to diagnose the system for Possible Causes 1, 2 and 3.
6. A short to ground in Circuit 611 (W/O) or 612 (P/O) may result in a blown fuse 7.
7. An internal short to ground within the LH kick panel safing rear air bag sensor and bracket may result in a blown fuse 7.
8. A short to ground on the battery feed circuit 937(R/W) between the fuse and Pin 13 of the air bag diagnostic monitor may result in a blown fuse 7.
9. A concern in the charging system causing battery voltage to drop below 9 volts.
