ELECTRICAL TYPE POWER HEATER SYSTEM TERMINALS OF ECU


  1. CHECK AIR CONDITIONING AMPLIFIER (w/ Quick Heater Assembly)

    A005KCCE02

    Tech Tips

    Check from the rear of the connector while it is connected to the air conditioning amplifier.

    Standard
    Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
    F41-8 (TX+) - F41-23 (GND) V - W-B CAN communication line Ignition switch: ON

    Pulse generation

    (see waveform 1)
    F41-9 (TX-) - F41-23 (GND) W - W-B CAN communication line Ignition switch: ON

    Pulse generation

    (see waveform 2)
    F41-1 (IG+) - F41-23 (GND) V - W-B Power source (IG) Ignition switch: ON 11 to 14 V
    F41-17 (SBLW) - F41-23 (GND) GR - W-B Blower motor ON signal Ignition switch: ON 11 to 14 V → 0 V
    Blower switch: 0 → 1
    F41-23 (GND) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
    F41-13 (PTC1) - Body ground SB - Body ground PTC heater relay operation signal Engine idling 11 to 14 V → Below 1 V
    Set temperature: MAX HOT
    Engine coolant temperature: Below 75°C (167°F)
    Ambient temperature: Below 10°C (50°F)
    Blower switch: OFF → LO
    F41-19 (PTC2) - Body ground P - Body ground PTC heater relay operation signal Engine idling 11 to 14 V → Below 1 V
    Set temperature: MAX HOT
    Engine coolant temperature: Below 70°C (158°F)
    Ambient temperature: Below 10°C (50°F)
    Blower switch: OFF → LO
    F41-20 (PTC3) - Body ground V - Body ground PTC heater relay operation signal Engine idling 11 to 14 V → Below 1 V
    Set temperature: MAX HOT
    Engine coolant temperature: Below 65°C (149°F)
    Ambient temperature: Below 10°C (50°F)
    Blower switch: OFF → LO

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


    1. A005JWRE01
      *a 1 V/DIV.
      *b 10 μsec./DIV.

      Waveform 1 (Reference) : Using an oscilloscope

      CAN Communication Signal
      Terminal Name F41-8 (TX+) - F41-23 (GND)
      Tester Range 1 V / DIV., 10 μsec. / DIV.
      Condition Ignition switch ON

      Tech Tips

      The waveform varies depending on the CAN communication signal.

    2. A005LZ2E01
      *a 1 V/DIV.
      *b 10 μsec./DIV.

      Waveform 2 (Reference) : Using an oscilloscope

      CAN Communication Signal
      Terminal Name F41-9 (TX-) - F41-23 (GND)
      Tester Range 1 V / DIV., 10 μsec. / DIV.
      Condition Ignition switch ON

      Tech Tips

      The waveform varies depending on the CAN communication signal.

  2. CHECK COMBINATION METER ASSEMBLY

    A005LLEE02
    Standard
    Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
    F1-39 (IG+) - Body ground P - Body ground Power source (IG) Ignition switch ON 11 to 14 V
    F1-40 (B) - Body ground L - Body ground Power source (Back-up) Always 11 to 14 V
    F1-34 (TX1-) - F1-35 (TX1+)* B - W Ambient temperature sensor signal Ignition switch ON at 25°C (77°F) 1.35 to 1.75 V

    *: w/ Quick Heater Assembly

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