CLIMATE CONTROL SEAT SYSTEM TERMINALS OF ECU


  1. AIR CONDITIONING AMPLIFIER ASSEMBLY


    1. Disconnect the H55 air conditioning amplifier assembly connector.

      A01W5KQE03

    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.

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      H54-21 (B) - Body ground GR - Body ground Air conditioning amplifier power supply Always 11 to 14 V
      H54-1 (IG+) - Body ground V - Body ground Air conditioning amplifier power supply Engine switch on (IG) 11 to 14 V
      H54-14 (GND) - Body ground W-B - Body ground Air conditioning amplifier 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 H55 air conditioning amplifier assembly connector.

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

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      H55-7 (SG-5) - Body ground R - Body ground Refreshing seat switch ground Always Below 1 Ω
      H55-9 (S5-2) - Body ground L - Body ground Refreshing seat switch power source Engine switch on (IG) 4.5 to 5.5 V
      H55-18 (SVDS) - Body ground

      B - Body ground*1

      GR - Body ground*2

      		 Refreshing seat switch volume (for LH) signal

      Refreshing seat switch volume (for LH) between 0 and 3

      (blower position)

      		 0 to 5 V
      H55-19 (SVPS) - Body ground

      GR - Body ground*1

      B - Body ground*2

      		 Refreshing seat switch volume (for RH) signal

      Refreshing seat switch volume (for RH) between 0 and 3

      (blower position)

      		 0 to 5 V
      H55-10 (SVDB) - Body ground

      LG - Body ground*1

      V - Body ground*2

      		 Climate control blower control signal

      Engine switch on (IG), refreshing seat switch (for RH) on

      (blower position)

      Pulse generation

      (See waveform)
      H55-11 (SVPB) - Body ground

      V - Body ground*1

      LG - Body ground*2

      		 Climate control blower control signal

      Engine switch on (IG), refreshing seat switch (for LH) on

      (blower position)

      Pulse generation

      (See waveform)

      • *1: for LHD

      • *2: for RHD

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


      1. A01W5QUE06

        Waveform (Reference): Using an oscilloscope:

        Tester Connection

        H55-10 (SVDB) - Body ground

        H55-11 (SVPB) - Body ground
        Tool Setting 1 V/DIV., 1 msec/DIV.
        Vehicle Condition

        Engine switch on (IG), refreshing seat switch on

        (blower position)