TIRE PRESSURE WARNING SYSTEM TERMINALS OF ECU


  1. CHECK TIRE PRESSURE WARNING ECU AND RECEIVER


    1. A01WQISE02
      Text in Illustration
      *A w/o Front Antenna
      *B w/ Front Antenna
      *a

      Front view of wire harness connector

      (to Tire Pressure Warning ECU and Receiver)

      Disconnect the L69*1 or L82*2 tire pressure warning ECU and receiver connector and measure the voltage and resistance on the wire harness side.


      • *1: w/o Front Antenna

      • *2: w/ Front Antenna

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition

      L69-1 (IG) - L69-12 (GND)*1

      L82-1 (IG) - L82-12 (GND)*2

      		 B - BR IG power source Engine switch on (IG) 10 to 16 V
      L69-7 (+B) - L69-12 (GND)*1 R - BR Power supply (from battery) Always 10 to 16 V

      L69-9 (CANH) - L69-10 (CANL)*1

      L82-9 (CANH) - L82-10 (CANL)*2

      		 R - W CAN communication line Engine switch off 54 to 69 Ω

      L69-12 (GND) - Body ground*1

      L82-12 (GND) - Body ground*2

      		 BR - Body ground Ground Always Below 1 Ω

      • *1: w/o Front Antenna

      • *2: w/ Front Antenna

    2. Connect the L69*1 or L82*2 tire pressure warning ECU and receiver connector.


      • *1: w/o Front Antenna

      • *2: w/ Front Antenna

    3. Measure the voltage and resistance according to the value(s) in the table below. If the result is not as specified, the ECU may be malfunctioning.

      Tech Tips

      Measure the values on the wire harness side while the connector is connected.

      A01WSKUE02
      Text in Illustration
      *A w/o Front Antenna *B w/ Front Antenna
      *a

      Component with harness connected

      (Tire Pressure Warning ECU and Receiver)

      		 - -
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition

      L69-3 (CLSW) - L69-12 (GND)*1

      L82-3 (CLSW) - L82-12 (GND)*2

      		 W - BR Tire pressure warning reset switch

      • Engine switch on (IG)

      • Tire pressure warning reset switch on

      		 Below 1.5 V

      • Engine switch on (IG)

      • Tire pressure warning reset switch off

      		 8 to 15 V

      L69-4 (RDA) - L69-12 (GND)*1

      L82-4 (RDA2) - L82-12 (GND)*2

      		 G - BR Output signals Engine switch on (IG) Pulse generation (see waveform 1)

      L69-5 (PRG) - L69-12 (GND)*1

      L82-5 (PRG2) - L82-12 (GND)*2

      		 L - BR Input signals Engine switch on (IG) Pulse generation (see waveform 1)

      • *1: w/o Front Antenna

      • *2: w/ Front Antenna

    4. A01WUA4E01
      Text in Illustration
      *a Example
      *b GND

      Using an oscilloscope, check waveform 1.

      Waveform 1:
      Item Contents
      Terminal

      L69-4 (RDA) - L69-12 (GND)*1

      L82-4 (RDA2) - L82-12 (GND)*2

      L69-5 (PRG) - L69-12 (GND)*1

      L82-5 (PRG2) - L82-12 (GND)*2
      Tool setting 5 V/DIV, 50 μs./DIV.
      Vehicle condition Engine switch on (IG)

      • *1: w/o Front Antenna

      • *2: w/ Front Antenna

      Tech Tips

      The waveform shown in the illustration is an example. If the tester displays a waveform that alternates between high and low, where high is a voltage that is between the IG power source voltage and a voltage 2.2 V lower than the IG power source voltage, and where low is a voltage of between 0 and 1.2 V, the ECU can be judged normal.