No Response From Transmission Control Module (TCM)
NOTE:
After making any repairs, perform TRANSMISSION VERIFICATION TEST
under VERIFICATION TESTS.
- Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, attempt to communicate with Body Control Module (BCM). If scan tool communicates with BCM, go to next step. If scan tool does not communicate with BCM, repair communication concern. See NO RESPONSE FROM BODY CONTROL MODULE (BUS +/- SIGNAL OPEN) .
- Using scan tool, retrieve Diagnostic Trouble Codes (DTCs) from all module. If no DTCs exist, go to next step. If any DTCs exist, perform appropriate test. See DIAGNOSTIC TROUBLE CODE IDENTIFICATION table under SELF-DIAGNOSTIC SYSTEM.
- Using scan tool, attempt to communicate with all other modules. If scan tool communicates with all other modules, go to next step. If scan tool does not communicate with all other modules, perform appropriate test. See DIAGNOSTIC TROUBLE CODE IDENTIFICATION table under SELF-DIAGNOSTIC SYSTEM.
- Turn ignition off. Disconnect Transmission Control Module (TCM) harness connector. Turn ignition on. Measure voltage at terminal No. 11 (Red/White wire) at TCM harness connector. See Fig 1 . If battery voltage exists, go to next step. If battery voltage does not exist, repair power distribution circuit as necessary. See POWER DISTRIBUTION article in WIRING DIAGRAMS.
- Remove starter relay in Power Distribution Center (PDC). See Fig 2 . Measure voltage at terminal No. 8 (Yellow wire) at TCM harness connector while turning ignition switch to start position. If battery voltage exists, go to next step. If battery voltage does not exist, repair power distribution circuit as necessary. See POWER DISTRIBUTION article in WIRING DIAGRAMS.
- Turn ignition off. Measure voltage at terminal No. 56 (Red/Light Blue wire) at TCM harness connector. If battery voltage exists, go to next step. If battery voltage does not exist, repair power distribution circuit as necessary. See POWER DISTRIBUTION article in WIRING DIAGRAMS.
- Turn ignition off. Measure resistance between ground and terminals No. 53 (Black wire) and No. 57 (Black/Red wire) at TCM harness connector. If both resistances are 5 ohms or less, go to next step. If any resistance is greater than 5 ohms, repair open in appropriate wire between ground and TCM.
- Turn ignition off. Disconnect Body Control Module (BCM) harness connector C3. Measure resistance in Violet/Yellow wire between terminal No. 43 at TCM harness connector and terminal No. 7 at BCM harness connector C3. See Figure and Fig 1 . If resistance is greater than 5 ohms, repair open in Violet/Yellow wire between TCM and BCM. If resistance is 5 ohms or less, replace TCM.