Diagnosis And Testing - Heated Seat Module

One heated seat module is located under each front seat. The drivers side module controls the drivers heated seat and the passenger controls the passenger heated seat. The first step in the testing procedure is to locate the suspect module and unsnap it from the appropriate seat cushion pan. After the module is visible, disconnect the modules electrical connector. Perform the following tests, Refer to appropriate SYSTEM WIRING DIAGRAMS article for the location of complete heated seat system wiring diagrams.

1. Check for 12 volts at the Fused B+ terminal of the heated seat control module electrical connector. If OK go to Step 2. If not OK, check the heated seat cut-out relay, located in the Power Distribution Center.
2. Turn the ignition switch "ON" and check for 12 volts at the switched ignition feed terminal of the heated seat control module electrical connector. If OK go to Step 3. If not OK, check the ignition feed circuit for shorts or opens.
3. Check for continuity between a known good ground and the ground wire terminal of the heated seat control module electrical connector. If OK go to step 4. If not OK, carefully inspect the harness for an open or short.
4. Check the heated seat switch input terminal of the heated seat control module electrical connector for the proper MUX signal (resistance range of 0-500 ohms, refer to DIAGNOSIS AND TESTING - HEATED SEAT SWITCH ). If OK replace the heated seat module. If not OK, test the heated seat switch and harness as described in the service information.