Self Test/Continuous Memory and Clear DTCs

SELF TEST/CONTINUOUS MEMORY AND CLEAR DTCs

The continuous memory DTC, is a DTC that at some point was an on-demand DTC. The continuous memory DTC is useful in determining an area of concern within the supplemental restraint system (SRS).

During vehicle operation, the restraints control module (RCM) will detect and store both intermittent (continuous memory) and hard failure DTCs in non-volatile memory.

The DTC strategy employed by the RCM incorporates a time-out scheme for determining when a concern exists in the system. This requires a concern to mature for up to one minute in the system before the RCM will store a DTC. For the RCM to determine that a concern no longer exists, the concern must be absent for up to one minute. The actual detection time-outs vary with each DTC. DTCs can be retrieved with a scan tool using the Self Test option. All DTCs stored in the RCM will be displayed on the scan tool along with a brief description of the DTC. If no DTCs are present, the scan tool will display a SYSTEM PASSED message. This option can also be used to clear DTCs from the RCM memory, as long as the concern no longer exists.

Once 75 hours of operation have been recorded by the RCM since the concern was last detected, all continuous memory DTCs will automatically be removed from memory.

To retrieve or clear continuous memory DTCs, follow these steps:
1. Connect the scan tool to the DLC.
2. Turn the ignition switch to the ON position.
3. Follow the manufacturer's instructions for the scan tool being used.
4. Select Self Test.
5. Select RCM.

6. NOTE: Before proceeding with the clearing operation, make note of the DTCs displayed. Once cleared, DTCs cannot be retrieved.

All on-demand and continuous memory DTCs will be displayed on the screen.

7. Select Clear DTCs.
8. Clear the DTCs. After clearing the DTCs, cycle the key OFF, then ON.
- Continuous memory DTCs that have been cleared will not reoccur as "continuous memory" in the same key cycle. Only new DTCs which were not present before clearing can occur as "continuous memory" after clearing.