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No Response From Transmission Control Module - Gas Only

Possible Causes are:

NOTE: Ensure there is PCI Bus communication with other modules on the vehicle before proceeding. If not, refer to COMMUNICATIONS in DIAGNOSTIC TROUBLE CODE IDENTIFICATION  and SYMPTOM IDENTIFICATION  tables under RETRIEVING & CLEARING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM.
  1. Ignition on, engine not running. As soon as one or more module communicates with the DRBIII(R), answer the question. Using the DRBIII(R), attempt to communicate with the Airbag Control Module (ACM). Using the DRBIII(R), attempt to communicate with the Body Control Module (BCM). Was the DRBIII(R) able to I/D or establish communications with either of the modules? If yes, go to next step. If no, go to PCI BUS COMMUNICATION FAILURE  . Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  2. Turn the ignition off to the lock position. Disconnect the TCM 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. See WIRING DIAGRAMS  . Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  3. Turn the ignition off to the lock position. Disconnect the TCM harness connector. Remove the starter relay from the PDC. Using a 12-volt test light connected to ground, check the Fused Ignition Switch Output (Start) circuit. The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery. Observe the test light while momentarily turning the ignition switch to the Start position. Does the test light illuminate brightly? If yes, go to next step. If no, repair the Fused Ignition Switch Output (Start) circuit for an open. See WIRING DIAGRAMS  . Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  4. Reinstall the original starter relay. Turn ignition off. Disconnect the TCM harness connector. Using a 12-volt test light connected to ground, check the Fused B (+) 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 B (+) circuit for an open. See WIRING DIAGRAMS  . Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  5. Turn the ignition off to the lock position. Disconnect the TCM harness connector. Using a 12-volt test light connected to 12 volts, check each 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 at all the ground circuits? If yes, go to next step. If no, repair the Ground circuit(s) for an open. Check the main ground connection to engine block and/or chassis. Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  6. Disconnect the TCM harness connector. Use Scope Input Cable (CH7058), Cable To Probe Adapter (CH7062), and the Red and Black test probes. Connect the scope input cable to the channel one connector on the DRBIII(R). Attach the Red and Black leads and the cable to probe adapter to the scope input cable. Using the DRBIII(R), select Pep Module Tools. Select lab scope. Select Live Data. Select 12-volt square wave. Press F2 for Scope. Press F2 and use the down arrow to set voltage range to 20 volts. Set Probe to x10. Press F2 again, when complete. Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Bus circuit in the TCM connector. Turn ignition on. Observe the voltage display on the DRBIII(R) Lab Scope. Does the voltage pulse from 0 to approximately 7.5 volts? If yes, go to next step. If no, repair the PCI Bus circuit for an open. Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  7. If there are no possible causes remaining, replace the Transmission Control Module. Using the DRBIII(R), perform QUICK LEARN. Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST VER 1  under VERIFICATION TESTS.
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