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Scan Tool Does Not Communicate With Memory Seat Module (MSM)

  1. If a second vehicle of the same make, model and year is available, connect scan tool to second vehicle. Attempt to establish communications with second vehicle. If scan tool communicates with second vehicle, go to step  3 . If scan tool will not communicate with second vehicle, go to next step.
  2. If scan tool does not operate properly, scan tool is at fault. See scan tool user's manual.
  3. Disconnect driver's seat adjuster memory module connector C1. Using DVOM, measure resistance of Brown/White wire between memory module connector C1 terminal No. 6 and Data Link Connector (DLC) terminal No. 7. If resistance is 5 ohms or less, go to step  5 . If resistance is greater than 5 ohms, go to next step.
  4. Repair open or short in Brown/White wire between memory module connector C1 terminal No. 6 and DLC terminal No. 7. After repair is complete, go to step  22 .
  5. Using DVOM, measure resistance between ground and DLC connector terminal No. 7 (Brown/White wire). If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, go to step  13 .
  6. Disconnect Engine Control Module (ECM). Using DVOM, measure resistance between ground and DLC terminal No. 7 (Brown/White wire). If resistance is 5 ohms or less, go to step  8 . If resistance is greater than 5 ohms, go to next step.
  7. Replace ECM. See ENGINE CONTROL MODULE (ECM)  under REMOVAL & INSTALLATION. Go to step  22 .
  8. Disconnect instrument panel cluster. Using DVOM, measure resistance between ground and DLC terminal No. 7 (Brown/White wire). If resistance is 5 ohms or less, go to step  10 . If resistance is greater than 5 ohms, go to next step.
  9. Replace instrument panel cluster. See appropriate ANALOG INSTRUMENT PANELS article. Go to step  22 .
  10. Disconnect Transmission Control Module (TCM). Using DVOM, measure resistance between ground and DLC terminal No. 7 (Brown/White wire). If resistance is 5 ohms or less, go to step  12 . If resistance is greater than 5 ohms, go to next step.
  11. Replace TCM. See TRANSMISSION CONTROL MODULE (TCM)  under REMOVAL & INSTALLATION. Go to step  22 .
  12. If instrument panel cluster and all control modules are disconnected and short to ground still exists, repair short to ground in Brown/White wire. See WIRING DIAGRAMS  . Go to step  22 .
  13. Using DVOM, measure voltage between ground and DLC terminal No. 7 (Brown/White wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  21 .
  14. Disconnect Engine Control Module (ECM). Using DVOM, measure voltage between ground and DLC terminal No. 7 (Brown/White wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  16 .
  15. Replace ECM. See ENGINE CONTROL MODULE (ECM)  under REMOVAL & INSTALLATION. Go to step  22 .
  16. Disconnect instrument panel cluster. Using DVOM, measure voltage between ground and DLC terminal No. 7 (Brown/White wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  19 .
  17. Replace instrument panel cluster. See appropriate ANALOG INSTRUMENT PANELS article. Go to step  22 .
  18. Disconnect Transmission Control Module (TCM). Using DVOM, measure voltage between ground and DLC terminal No. 7 (Brown/White wire). If battery voltage exists, go to next step. If battery voltage does not exist, go to step  20
  19. If instrument panel cluster and all control modules are disconnected and short to ground still exists, repair short to ground in Brown/White wire. See WIRING DIAGRAMS  . Go to step  22 .
  20. Replace TCM. See TRANSMISSION CONTROL MODULE (TCM)  under REMOVAL & INSTALLATION. Go to step  22 .
  21. Check power and ground circuits for adjuster memory module. If all circuits are okay, replace driver seat adjuster memory module. See MEMORY MODULE  under REMOVAL & INSTALLATION. Go to next step.
  22. Reattach connectors to all modules and instrument panel cluster. Connect scan tool to DLC. If scan tool communicates with driver seat adjuster memory module, repair is complete. If scan tool does not communicate with driver seat adjuster memory module, go to step  1 .
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