METER / GAUGE SYSTEM Speedometer Malfunction

DESCRIPTION

The meter ECU receives the vehicle speed signal from the skid control ECU via the CAN communication system. The speed sensors detect the wheel speed and send signals to the skid control ECU. The skid control ECU supplies power to the vehicle speed sensors. The skid control ECU creates the vehicle speed signal based on the pulses of the voltage.

Tech Tips


  • Factors that affect the indicated vehicle speed include tire size, tire inflation, and tire wear. The speed indicated on the speedometer has an allowable margin of error. This can be tested using the GTS. For details about testing and the margin of error, see the reference chart Click here.

  • If the vehicle speed sensor circuit has a malfunction, the skid control ECU stores DTCs. Troubleshoot Electronically Controlled Brake System Click here.

WIRING DIAGRAM

A0041UAE81

INSPECTION PROCEDURE

Note

If the vehicle speed is outside the allowable range when tested, perform the on-vehicle inspection Click here.

Tech Tips

Before starting the following inspection, check tire size and tire air pressure.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if CAN communication DTC is output Click here.

      Result
      Result Proceed to
      CAN communication DTC is not output. A
      CAN communication DTC is output. B

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  2. PERFORM ACTIVE TEST USING GTS (SPEED METER OPERATION)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Combination Meter / Active Test.

    5. Check the operation by referring to the table below.

      Combination Meter
      Tester Display Test Part Control Range Diagnostic Note
      Speed Meter Operation Speedometer OFF, 0, 40, 80, 120, 160, 200, 240, 280 mph*1 Confirm that the vehicle is stopped with the engine idling
      OFF, 0, 40, 80, 120, 160, 200, 240, 280 km/h*2

      • *1: with mph units

      • *2: with km/h units

      OK
      Speedometer indication is normal.

    NG

    REPLACE NO. 3 METER CIRCUIT PLATE Click here

    OK

  3. CHECK ELECTRONICALLY CONTROLLED BRAKE SYSTEM


    1. Check if the electronically controlled brake system DTCs are output Click here.

      Result
      Result Proceed to
      DTCs are not output. A
      DTCs are output. B

    B

    REPLACE NO. 3 METER CIRCUIT PLATE Click here

    A

  4. READ VALUE USING GTS (VEHICLE SPEED, VEHICLE SPEED METER)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus:


      1. for ABS/VSC/TRAC: Chassis / ABS/VSC/TRC / Data List.

      2. for Combination Meter: Body Electrical / Combination Meter / Data List.

    5. Check the values by referring to the table below.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Vehicle Speed Maximum wheel speed sensor/Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph) Vehicle stopped: 0 km/h (0 mph) When driving at constant speed: No large fluctuations
      Combination Meter
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Vehicle Speed Meter Vehicle speed/Min.: 0 mph (0 km/h), Max.: 255 km/h (158 mph) Almost the same as actual vehicle speed (Speedometer tester) -
      Result
      Result Proceed to
      The data list values of the ECUs match. A
      The data list values of the ECUs do not match. B

      Tech Tips


      • When the Data List values of the ECUs match, an internal malfunction of the combination meter assembly is suspected.

      • When the Data List values of the ECUs do not match, a signal output error of the skid control ECU or an internal malfunction of the combination meter assembly is suspected.


    NG

    REPLACE METER CIRCUIT PLATE Click here

    OK

    REPLACE NO. 3 METER CIRCUIT PLATE Click here

  5. REPLACE METER CIRCUIT PLATE


    1. Replace the meter circuit plate with a new or known good one Click here.

      OK
      The operation of the speedometer returns to normal.

    NG

    REPLACE NO. 4 METER CIRCUIT PLATE Click here

    OK

    END

  6. REPLACE NO. 4 METER CIRCUIT PLATE


    1. Replace the No. 4 meter circuit plate with a new or known good one Click here.

      OK
      The operation of the speedometer returns to normal.

    NG

    REPLACE NO. 3 METER CIRCUIT PLATE Click here

    OK

    END

  7. REPLACE NO. 3 METER CIRCUIT PLATE


    1. Replace the No. 3 meter circuit plate with a new or known good one Click here.

      OK
      The operation of the speedometer returns to normal.
      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    B

    REPLACE SKID CONTROL ECU Click here

    C

    REPLACE SKID CONTROL ECU Click here

    A

    END