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Terminals Of Ecu

  1. CHECK FRONT LIGHT ECU (FRONT CONTROLLER) 
    Fig 1: Identifying A50, A51, A52 And B14 ECU Connector Terminals
    G04951346Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A50, A51, A52 and B14 ECU connectors.
    2. Measure the resistance and voltage according to the value(s) in the table below.
      TERMINAL DESCRIPTION REFERENCE CHART

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      A52-5 (ALTB) - Body ground L - Body ground +B power supply Always 11 to 14 V
      A52-1 (BATB) - Body ground P - Body ground +B power supply Always 11 to 14 V
      A50-1 (FMB3) - Body ground LG - Body ground +B power supply Always 11 to 14 V
      A50-5 (FMIG) - Body ground Y - Body ground IG power supply Engine switch on (IG) 11 to 14 V
      A50-2 (E) - Body ground W-B - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction on the wire harness side.

    3. Reconnect the A50, A51, A52 and B14 ECU connectors.
    4. Measure the voltage according to the value(s) in the table below.
      TERMINAL DESCRIPTION REFERENCE CHART

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      B14-1 (HORL) - Body ground G - Body ground Horn (low pitched) signal Horn is sounding 11 to 14 V
      B14-2 (HORH) - Body ground G - Body ground Horn (high pitched) signal Horn is sounding 11 to 14 V

      If the result is not as specified, the ECU may have a malfunction.

  2. CHECK STEERING PAD ECU (STEERING PAD SWITCH) 
    Fig 2: Identifying Z7 ECU Connector Terminals
    G04945755Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the z7 ECU connector.
    2. Measure the voltage according to the value(s) in the table below.
      TERMINAL DESCRIPTION REFERENCE CHART

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      z7-10 (+B) - Body ground B - Body ground +B power supply Always 11 to 14 V

      If the result is not as specified, there may be a malfunction on the wire harness side.