DTC 75

DTC 75: MCM Communication Signal Circuit Problem

NOTE: Information marked with an asterisk (*) applies to METSCI 2 line.
1. Reset the MCM.
2. Turn the ignition switch ON (II).
Is DTC 75 indicated?
YES- Go to step 3.
NO- Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the gauge assembly, BCM module and at the MCM.
3. Turn the ignition switch OFF.
4. Turn the battery module switch OFF.
5. Remove the IPU lid.
6. Disconnect MCM connector C (31P), BCM module connector A (26P) and the gauge assembly 22P connector.





7. Check for continuity between body ground and MCM connector terminals C10 and C9* individually.
Is there continuity?
YES- Repair short in the wire between the MCM (C10 or C9*) and the BCM module (A21 or AS*).
NO- Go to step 8.





8. Check for continuity between the BCM module connector terminal A21 and MCM connector terminal C10, and between BCM module connector terminals A8* and MCM connector terminal C9*.
Is there continuity?
YES- Substitute a known-good MCM and BCM module, and recheck. If the symptom/indication goes away, replace the original MCM and BCM module.
NO- Repair open in the wire between the MCM (C10, C9*) and the BCM module (A21, A8*).