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Inspection Procedure

NOTE: When using the intelligent tester (with CAN VIM) or Techstream with the engine switch off to troubleshoot:
Connect the intelligent tester (with CAN VIM) or Techstream to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the tester and vehicle begins.
  1. CLEAR DTC 
    1. Delete the DTC (see DTC CHECK / CLEAR  ).
  2. CHECK FOR DTC 
    1. Recheck for DTC (see DTC CHECK / CLEAR  ).

      Result: 

      RESULT

      Result Proceed to
      DTC U1127, U1128 and U1129 output occurs A
      DTC U1127, U1128 or U1129 output occurs B
      No DTC output occurs C

    B: GO TO  DTC CHART  

    C: USE SIMULATION METHOD TO CHECK  (See HOW TO PROCEED WITH TROUBLESHOOTING )

    A: GO TO NEXT STEP 

  3. CHECK HARNESS AND CONNECTOR (OUTER MIRROR SWITCH - NO. 1 CONSOLE SWITCH) 
    1. Disconnect the L6 and L75 switch connectors.
    2. Measure the resistance and voltage according to the value(s) in the table below.

      Standard resistance 

      OUTER MIRROR SWITCH - NO. 1 CONSOLE SWITCH RESISTANCE

      Tester Connection Condition Specified Condition
      L6-7 (MPX) - L75-3 (MPX) Always Below 1 Ω
      L6-7 (MPX) or L75-3 (MPX) - Body ground Always 10 kΩ or higher

      Standard voltage 

      OUTER MIRROR SWITCH - NO. 1 CONSOLE SWITCH VOLTAGE

      Tester Connection Condition Specified Condition
      L6-7 (MPX) or L75-3 (MPX) - Body ground Always Below 1 V
      Fig 1: Identifying L6 And L75 Switch Connectors
      G04947032Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE OUTER MIRROR SWITCH  (See REMOVAL )

    NG: GO TO NEXT STEP 

  4. CLEAR DTC 
    1. Reconnect the L6 switch connector.
    2. Delete the DTC (see DTC CHECK / CLEAR  ).
  5. CHECK FOR DTC 
    1. Disconnect the L75 switch connector.
    2. Recheck for DTC (see DTC CHECK / CLEAR  ).

      Result: 

      RESULT

      Result Proceed to
      DTC U1127, U1128 and U1129 output occurs A
      DTC U1127 output occurs B

    B: REPLACE NO. 1 CONSOLE SWITCH 

    A: GO TO NEXT STEP 

  6. CLEAR DTC 
    1. Reconnect the L75 switch connector.
    2. Delete the DTC (see DTC CHECK / CLEAR  ).
  7. CHECK FOR DTC 
    1. Disconnect the e4 ECU connector.
    2. Recheck for DTC (see DTC CHECK / CLEAR  ).

      Result: 

      RESULT

      Result Proceed to
      DTC U1127, U1128 and U1129 output occurs A
      DTC U1128 output occurs B

    B: REPLACE FRONT SEAT CLIMATE CONTROL ECU RH 

    A: GO TO NEXT STEP 

  8. CLEAR DTC 
    1. Reconnect the e4 ECU connector.
    2. Delete the DTC (see DTC CHECK / CLEAR  ).
  9. CHECK FOR DTC 
    1. Disconnect the e34 ECU connector.
    2. Recheck for DTC (see DTC CHECK / CLEAR  ).

      Result: 

      STANDARD RESISTANCE

      Result Proceed to
      DTC U1127, U1128 and U1129 output occurs A
      DTC U1129 output occurs B

    B: REPLACE FRONT SEAT CLIMATE CONTROL ECU LH 

    A: REPAIR OR REPLACE HARNESS OR CONNECTOR