Loss Of Engine RPM Message
NOTE:
After making any repairs, perform MEMORY HEATED SYSTEM VERIFICATION TEST
under VERIFICATION TESTS.
Monitored & Set Condition
- When Monitored: With the engine running.
- Set Condition: When the Memory Heated Seat Mirror Module does not receive the engine RPM Bus message.
Possible Causes:
- Stored Code/Communication Problems
- Memory Heated Seat Mirror Module
- Intermittent Problem
Testing
- Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, clear LOSS OF ENGINE RPM DTC from memory heated seat/mirror module. Turn ignition off, then start engine. Wait one minute. Using scan tool, retrieve DTCs. If LOSS OF ENGINE RPM DTC resets, go to next step. If LOSS OF ENGINE RPM DTC does not reset, test is complete. Perform MEMORY HEATED SYSTEMS VERIFICATION TEST under VERIFICATION TESTS.
- Check related wiring and connectors for poor connections or damage to wiring harness. See WIRING DIAGRAMS . Repair any problems found as necessary. If no problems are found, replace MHSMM. See MEMORY HEATED SEAT/MIRROR MODULE under REMOVAL & INSTALLATION.