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Scan Tool Does Not Communicate With TDM

  1. Perform IMMOBILIZER SYSTEM CHECK  . Go to next step.
  2. Check scan tool operation on another vehicle. If scan tool is okay, go to next step. If scan tool does not work, replace scan tool.
  3. Disconnect TDM connector. Check resistance of Brown/White wire between DLC terminal No. 3 and TDM harness connector terminal No. 8. If resistance is less than 5 ohms, go to next step. if resistance is 5 ohms or more, repair open or high resistance in Brown/White wire. Go to step 11).
  4. Check resistance of Brown/White wire between DLC terminal No. 3 and ground. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, go to step 7).
  5. Disconnect sun roof actuator connector. Recheck resistance of Brown/White wire between DLC terminal No. 3 and ground. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, sun roof actuator is internally shorted to ground. Replace actuator. See POWER SUN ROOF article. After repair, go to step 11).
  6. If all modules are disconnected and continuity still exists, repair short to ground in wiring. See WIRING DIAGRAMS  . After repair, go to step 11).
  7. Check voltage between DLC terminal No. 3 (Brown/White) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, go to step 10).
  8. Disconnect sun roof actuator connector. Recheck voltage between DLC terminal No. 3 (Brown/White) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, sun roof actuator is internally shorted to battery voltage. Replace actuator. See POWER SUN ROOF article. After repair, go to step 11).
  9. If all modules are disconnected and voltage still exists, repair short to battery voltage in wiring. After repair, go to step 11).
  10. Check all power and ground circuits to TDM. See WIRING DIAGRAMS  . Repair as necessary. Go to next step. If no problems were found, replace TDM. See THEFT DETERRENT MODULE (TDM)  under REMOVAL & INSTALLATION. Go to next step.
  11. Reconnect all components and connectors. Using scan tool, attempt communication with TDM. If communication exists, system is okay. If communication does not exist, return to step 1).
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