MHSMM Messages Not Received

Monitored & Set Condition

1. When Monitored: With the ignition in RUN position and the IOD fuse installed.
2. Set Condition: The BCM does not receive any messages from the Memory Heated Seat/Mirror Module (MHSMM) for at least 18 seconds.

Possible Causes:

• Attempt To Communicate With The Memory Heated Seat/Mirror Module
• Body Control Module

Testing

1. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, select BODY, then MEMORY SEAT MODULE. If scan tool communicates with Memory Heated Seat/Mirror Module (MHSMM), go to next step. If scan tool does not communicate with MHSMM, perform BUS +/- SIGNALS OPEN OR NO RESPONSE FROM MEMORY HEATED SEAT/MIRROR MODULE  test.
2. Using scan tool, clear DTCs. Turn ignition off. Turn ignition on and wait one minute. Using scan tool, retrieve DTCs. If MHSMM MESSAGES NOT RECEIVED DTC resets, replace BCM. See BODY CONTROL MODULE  under REMOVAL & INSTALLATION. If MHSMM MESSAGES NOT RECEIVED DTC does not reset, fault may be intermittent. 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, check if any Technical Service Bulletins (TSBs) apply to vehicle. If no TSBs apply, test is complete.