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Shift Light (Manual Transmission)

  1. If powertrain OBD system check has been performed, go to next step. If powertrain OBD system check has not been performed, perform powertrain OBD system check. See POWERTRAIN OBD SYSTEM CHECK in TESTS W/CODES - 6.5L TURBO DIESEL article.
  2. Turn ignition switch to LOCK position. Connect scan tool to data link connector. Turn ignition switch to RUN position. Using scan tool, command shift light on. If shift light does not illuminate, go to next step. If shift light illuminates, go to step 4).
  3. Turn ignition switch to LOCK position. Disconnect PCM harness connector that contains shift light circuit. Turn ignition switch to RUN position. Using a fused jumper wire, ground shift light control circuit (Tan/Black wire) at PCM harness connector. If shift light illuminates when grounded, go to step 5). If shift light does not illuminate, go to step 6).
  4. Using scan tool, command shift light off then on. If shift light operates as expected, system is okay at this time. If shift light does not operate as expected, go to step 8).
  5. Check for poor connection at PCM. If poor connection exists, go to step 7). If poor connection does not exist, go to step 10).
  6. Repair open in shift light control circuit and go to step 11).
  7. Repair poor connection as necessary and go to step 11).
  8. Turn ignition switch to LOCK position. Disconnect PCM harness connector that contains shift light circuit. Turn ignition switch to RUN position. If shift light illuminates, go to next step. If shift light does not illuminate, go to step 10).
  9. Repair short to ground in shift light control circuit (Tan/Black wire) between PCM and instrument cluster. After repair is complete, go to step 11).
  10. Replace PCM. Program PCM, perform VTD password relearn procedure and perform crankshaft variation learn procedure. See COMPUTER RELEARN PROCEDURES in GENERAL INFORMATION article. After repair is complete, go to next step.
  11. Start engine and let idle until normal operating temperature is obtained. Select DTC FAILED THIS IGNITION on scan tool. If DTCs do not exist, system is okay at this time. If DTCs exist, perform appropriate DTC test. See TESTS W/CODES - 6.5L TURBO DIESEL article.
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