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Home >> Toyota >> 2003 >> Highlander Base, 3.0 F, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self Diagnostics - V6 >> Self-Diagnostic System >> Retrieving Diagnostic Trouble Codes >> CHECK Mode Code Retrieval
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CHECK Mode Code Retrieval

  1. Ensure vehicle battery positive voltage is 11 V or more. Apply parking brake. Shift transaxle into Neutral (M/T) or Park (A/T). Turn A/C and all accessories off. Ensure throttle valve is fully closed. Turn ignition off. Connect hand-held tester to DLC3. See Figure. Turn ignition on and then turn hand-held tester on.
  2. Switch hand-held tester from normal mode to check mode. Ensure malfunction indicator light (MIL) on instrument cluster flashes to indicate check mode operation. Start engine. If no DTCs are present, MIL will turn off. Try to simulate conditions of driveability complaint described by customer.
    NOTE: Leave the ignition switch ON until you have checked the DTC, etc.
  3. After simulating the malfunction conditions, use the hand-held tester diagnosis selector to check the DTCs and freeze frame data, etc. If any DTCs are present, perform appropriate DTC test under DIAGNOSTIC TESTS . If driveability problem exists and no DTCs are present, go to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom. For information on freeze frame data, see FREEZE FRAME DATA . For information on two-trip detection logic codes, see TWO-TRIP DETECTION LOGIC .
  4. If any DTCs are present, perform appropriate DTC test under DIAGNOSTIC TESTS . For DTC description, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . For information on freeze frame data, see FREEZE FRAME DATA . For information on two-trip detection logic DTCs, see TWO-TRIP DETECTION LOGIC .
    NOTE: Be careful not to turn the ignition switch OFF. Turning the ignition switch OFF switches the diagnosis system from the check mode to the normal mode. So all the DTCs, etc. will be erased.
  5. After repairs for DTC have been completed, DTC must be cleared from ECM. See CLEARING DIAGNOSTIC TROUBLE CODES . Road test vehicle to ensure all symptoms and/or complaints have been repaired.
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