Air bag light, code 12

1993 MERCURY MARQUIS
96,000 MILES
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ANTHONY 2019
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My air bag light blinks once then a pauses, then blinks twice, which is a code 12. how can I fix this problem?
Jan 1, 2019 at 2:49 PM
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ASEMASTER6371
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Good evening,

The code 12 is for low voltage. I would have the battery checked and the charging system checked.

https://www.2carpros.com/articles/car-battery-load-test

https://www.2carpros.com/articles/how-to-check-a-car-alternator

Below is the description and a flow chart.

Roy

DIAGNOSTIC TROUBLE CODE 12

Low Battery Voltage

Normal Operation
The diagnostic monitor measures the voltage at Pin 13 of the 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 Diagnostic Trouble Code 12.

Possible Causes
Low battery voltage at diagnostic monitor Pin 13 can be caused by:
1. An open in Circuit 937 (R/W) that would prevent battery voltage from reaching diagnostic monitor Pin 13.
2. A short to ground in Circuit 611 (W/O) or 612 (P/O) may result in a blown instrument panel fuse 5.

NOTE: If the instrument panel fuse 5 is blown be sure to diagnose the system for Possible Causes 2 and 3.

3. An internal short to ground within the safing sensor may result in a blown instrument panel fuses.
4. A concern in the charging system causing battery voltage to drop below 9 volts.
Jan 1, 2019 at 4:16 PM