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Diagnosis & Repair

  1. Connect Toyota hand-held tester or scan tool to Data Link Connector (DLC) No. 3. See Figure. Attempt to retrieve DTCs from transmission control ECU. If hand-held tester or scan tool communicates with transmission control ECU and no DTCs exist, go to next step. If hand-held tester or scan tool communicates with transmission control ECU and DTCs exist, repair as necessary and retest system. See appropriate ELECTRONIC CONTROLS article in MANUAL TRANSMISSIONS.
  2. Check for open or short in Blue/Orange wire between terminal No. 85 at transmission control ECU harness connector and terminal No. 30 at ECM harness connector E5. See Figure and Fig 1 . If problem exists, repair wiring as necessary. If problem does not exist, replace ECM.
Fig 1: Identifying Transmission Control Electronic Control Unit Harness Connector Terminals
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