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CHECK Mode Diagnostic Trouble Code Retrieval

NOTE: If using Toyota hand-held tester, if ignition switch is turned from ON to ACC or OFF position during CHECK mode, all DTCs and freeze frame data will be erased from ECM. DO NOT switch from CHECK mode to NORMAL mode until all DTCs and freeze frame data are recorded.
  1. Ensure vehicle battery is fully charged. Apply parking brake. Place transaxle in Park or Neutral. Ensure A/C and ignition are off. Check that throttle valve is fully closed. Connect hand-held tester to Data Link Connector (DLC3) at driver's side of instrument panel. 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 exist, MIL will turn off. Try to simulate conditions of driveability complaint described by customer.
  3. Record any DTCs and freeze frame data displayed for system diagnosis. If driveability problem exists and no DTCs are present, go to TROUBLESHOOTING - NO CODES article for diagnosis by symptom. If no DTCs are present and no driveability problem exists but MIL is illuminated, a problem may exist in the Hybrid Vehicle (HV) control system. Consult authorized dealer for diagnosis of HV control system.
  4. If any DTCs are present, perform appropriate DTC test listed under DIAGNOSTIC TESTS. For DTC description, see DIAGNOSTIC TROUBLE CODE DEFINITIONS  under DIAGNOSTIC TROUBLE CODE DEFINITIONS. For information on freeze frame data, see FREEZE FRAME DATA . For information on two-trip detection logic codes, see TWO-TRIP DETECTION LOGIC .
  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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