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No Response From Transmission Control Module - Diesel Only

Possible Causes are:

  1. Turn ignition on. Using the DRBIII(R), attempt to communicate with the ECM. Was the DRBIII(R) able to I/D or communicate with the ECM? If yes, go to next step. If no, go to NO RESPONSE FROM ECM (SCI ONLY) - DIESEL ONLY  . Perform W5AJ400 TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  2. Turn the ignition off to the lock position. Disconnect the TCM C1 harness connector. Turn ignition on, engine not running. Using a 12-volt test light connected to ground, check the Fused Ignition Switch Output (Run/St) circuit. The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery. Does the test light illuminate brightly? If yes, go to next step. If no, repair the Fused Ignition Switch Output (Run/St) circuit for an open. Perform W5AJ400 TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  3. Turn the ignition off to the lock position. Disconnect the TCM C1 harness connector. Using a 12-volt test light connected to 12 volts, check the ground circuit in the TCM harness connector. The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery. Does the test light illuminate brightly? If yes, go to next step. If no, repair the ground circuit for an open. Perform W5AJ400 TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  4. Turn ignition off. Disconnect the TCM C1 harness connector. Disconnect the DRBIII(R) from the DLC. Measure the resistance of the SCI Transmit circuit between the TCM connector and the DLC. Is the resistance less than 5 ohms? If yes, replace the Transmission Control Module. Perform W5AJ400 TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS. If no, repair the SCI Transmit circuit for an open. Perform W5AJ400 TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
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