COMBUSTION TYPE POWER HEATER SYSTEM TERMINALS OF ECU


  1. CHECK HEATER ASSEMBLY

    B001HAPE02

    1. Measure the voltage, resistance and waveform according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A97-1 (E) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
      A97-2 (L) - Body ground R - Body ground Heater pump operation signal

      Engine idling

      Power heater switch on

      Pulse generation

      (See waveform 1)
      A97-3 (IG) - Body ground W - Body ground Power heater operating signal

      Engine switch on (IG)

      Power heater switch on

      		 11 to 14 V

      Engine switch on (IG)

      Power heater switch off

      		 Below 1 V
      A97-5 (B) - Body ground B - Body ground Power source Always 11 to 14 V
      A97-8 (+) - Body ground G - Body ground Engine operating signal Engine idling 11 to 14 V
    2. B001GB6E03

      Using an oscilloscope, check waveform 1.

      Heater Pump Control Signal
      Item Content
      Terminal No. (Symbol) A97-2 (L) - Body ground
      Tool Setting 2 V/DIV., 20 ms/DIV.
      Condition

      Engine idling

      Power heater switch on

  2. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY

    B001FXIE02

    1. Measure the voltage according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      G25-18 (HTR1) - G25-14 (GND) G - W-B Engine operating signal Engine idling 11 to 14 V