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Retrieve/Clear Continuous DTCs

During vehicle operation the Restraints Control Module (RCM) will detect and store both intermittent and hard failure DTCs in nonvolatile 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 exist for up to one minute in the system before the RCM will detect it. 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. The DTCs can be retrieved with the New Generation Star (NGS) Tester using the retrieve/clear continuous DTCs option. Any DTCs stored in the RCM will be displayed on the NGS Tester along with a brief description of the DTC. If no DTCs are present, the NGS Tester 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 254 key cycles have been recorded since the concern was last detected, the DTC will automatically be removed from memory.

To retrieve or clear DTCs, follow these steps:
1. Connect the NGS Tester to the Data Link Connector (DLC).
2. Turn the ignition switch to the RUN position.
3. Select the MODEL YEAR and VEHICLE.
4. Select DIAGNOSTIC DATA LINK.
5. Select RCM (Restraints Control Module).
6. Select DIAGNOSTIC TEST MODES.
7. Select RETRIEVE/CLEAR CONTINUOUS DTCs.
8. After pressing START, all continuous DTCs will be displayed on the screen. Before proceeding with the clearing operation, make note of the DTCs displayed, because once cleared, they cannot be retrieved.
9. To clear the DTCs, press ALL.
10. The NGS Tester will retrieve DTCs again after clearing DTCs, and if any remain they will be displayed. Hard DTCs will be redisplayed after clearing DTCs since they cannot be cleared from the RCM.