No Response From Transmission Control Module
NOTE:
After making any repairs, perform 41TE TRANSMISSION VERIFICATION TEST under VERIFICATION TESTS.
- Turn ignition on. Using scan tool, attempt to communicate with Occupant Restraint Controller (ORC) and Body Control Module (BCM). If scan tool identifies or communicates with any module, go to next step. If scan tool does not identify or communicate with any module, go to PCI BUS COMMUNICATION FAILURE .
- Turn ignition off. Disconnect Transmission Control Module (TCM). See COMPONENT LOCATIONS . Turn ignition on. Using a test light connected to ground, probe TCM connector terminal No. 11 (Pink/White wire). See Fig 1. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open in Pink/White wire between TCM and Front Control Module (FCM) connector terminal No. 27.
- Turn ignition off. Remove starter relay from Intelligent Power Module (IPM) located in left front of engine compartment. See Figure. Using a test light connected to ground, probe starter relay cavity terminal No. 86 while turning ignition switch from OFF to START position. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open in Yellow wire between ignition switch 5-pin connector terminal No. 4 and IPM connector C7 terminal No. 2 or open in internal IPM circuit between connector C7 and starter relay cavity terminal No. 86. See Fig 2.
- Using a test light connected to ground, probe TCM connector terminal No. 56 (Yellow/Red wire). If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open in Yellow/Red wire between TCM and fuse No. 15 (20-amp) located in IPM.
- Using a test light connected to battery voltage, probe TCM connector terminal No. 53 (Black/Yellow wire) and No. 57 (Black/Light Green wire). If test light illuminates brightly at both terminals, go to next step. If test light does not illuminate brightly at both terminals, repair open in suspect ground wire between TCM and splice S111 located near Powertrain Control Module (PCM).
- Obtain Scope Input Cable (CH7058), Cable To Probe Adapter (CH7062) and Red and Black test probes. Connect scope input cable to channel 1 connector on scan tool. Connect Red and Black test probes and probe adapter to scope input cable. Select PEP MODULE TOOLS on scan tool. Select LAB SCOPE then LIVE DATA. Select 12V SQUARE WAVE. Press F2 for scope then enter to select channel. Press F2 again and use down arrow to set voltage range to 20 volts. Set probe to x10. Press F2 again to complete. Connect Black probe to ground and Red probe to TCM connector terminal No. 43 (White/Violet wire). See Fig 1. Turn ignition on. Monitor scope on scan tool. If voltage pulses between zero and 7.5 volts, go to next step. If voltage does not pulse between zero and 7.5 volts, repair open in White/Violet wire (PCI bus circuit) between TCM and diagnostic junction port terminal No. 9. See Figure.
- Replace TCM. See TRANSMISSION CONTROL MODULE under REMOVAL & INSTALLATION.