WINDOW DEFOGGER SYSTEM TERMINALS OF ECU


  1. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY


    1. Disconnect the I77 air conditioning amplifier assembly connector.

      B000IUIE01
      Text in Illustration
      *A air conditioning amplifier assembly with 2 connectors *B air conditioning amplifier assembly with 3 connectors

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Tech Tips

      Measure the values on the wire harness side with the connector disconnected.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      I77-1 (IG+) - I77-14 (GND) B - W-B Power source (IG) Ignition switch ON 11 to 14 V
      I77-1 (IG+) - I77-14 (GND) B - W-B Power source (IG) Ignition switch off Below 1 V
      I77-21 (B) - I77-14 (GND) Y - W-B Battery power supply Always 11 to 14 V
      I77-14 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω

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

    3. Reconnect the I77 air conditioning amplifier assembly connector.

    4. Measure the voltage and check for pulses according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      I77-38 (RDFG) - I77-14 (GND)

      G*1 - W-B

      P*2 - W-B

      		 Rear window defogger signal Ignition switch ON, rear window defogger switch off 11 to 14 V
      I77-38 (RDFG) - I77-14 (GND)

      G*1 - W-B

      P*2 - W-B

      		 Rear window defogger signal Ignition switch ON, rear window defogger switch on Below 2.2 V
      I77-37 (LIN1) - I77-14 (GND) V - W-B LIN communication line Ignition switch ON Pulse generation

      • *1: for LHD

      • *2: for RHD

      If the result is not as specified, the air conditioning amplifier assembly may have a malfunction.

  2. CHECK AIR CONDITIONING PANEL (HEATER CONTROL SWITCH BOARD)


    1. Disconnect the I56 air conditioning panel (heater control switch board) connector.

      B000IPGE02

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Tech Tips

      Measure the values on the wire harness side with the connector disconnected.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      I56-2 (IG+) - I56-6 (GND) R - W-B Power source (IG) Ignition switch ON 11 to 14 V
      I56-2 (IG+) - I56-6 (GND) R - W-B Power source (IG) Ignition switch off Below 1 V
      I56-6 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω

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

    3. Reconnect the I56 air conditioning panel (heater control switch board) connector.

    4. Check for pulses according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      I56-9 (LIN1) - I56-6 (GND) V - W-B LIN communication line Ignition switch ON Pulse generation

      If the result is not as specified, the air conditioning panel (heater control switch board) may have a malfunction.