Operation CHARM: Car repair manuals for everyone.

Clearing Trouble Codes

Procedure to Clear Diagnostic Trouble Codes from Diagnostic Monitor Non-Volatile Random Access Memory.

Description
The air bag diagnostic monitor continually checks the air bag system for readiness. When a fault condition is detected, the DTC associated with that fault is stored in the air bag diagnostic monitor's Non-Volatile Random Access Memory (NVRAM). After writing the DTC to NVRAM, the air bag diagnostic monitor signals the fault by flashing the appropriate diagnostic trouble code on the air bag indicator.

The diagnostic trouble code written to NVRAM is permanently stored in the air bag diagnostic monitor until cleared by the diagnostic trouble code clearing procedure.

NOTE: Once a fault has been serviced, the associated diagnostic trouble code may be cleared from NVRAM. Only diagnostic trouble codes that the air bag diagnostic monitor sees as repaired or intermittent may be cleared (diagnostic trouble codes 52 and above). In no circumstances can hard fault conditions (diagnostic trouble codes 45 and below) be cleared.

Procedure
1. Follow the diagnostic procedures as outlined to service the fault condition flashing on the air bag indicator.

2. Cycle the ignition switch to OFF and then to RUN.

3. Observe air bag indicator prove-out (six seconds ±two seconds) followed by diagnostic trouble code (52-85) flashing completely one time.

4. Locate the Diagnostic "Trouble Code Clear" Connector located underneath the glove compartment containing Circuits 631 (T/R) and 57 (BK).

5. Use a jumper wire to short Circuit 631 (T/R) to Circuit 57 (BK) or to another good ground. This short must be made after the diagnostic trouble code flashes completely one time, but before the warning light stays on continuously.

6. Hold short until air bag diagnostic monitor tone sounds (approximately five seconds).

7. Release short on Circuit 631 (T/R) to Circuit 57 (BK). This short must be released within 25 seconds after the diagnostic monitor tone sounds.

Diagnostic trouble code is now cleared from NVRAM. Next highest priority diagnostic trouble code stored in NVRAM (if one exists) will begin flashing.