AUTOMATIC TRANSAXLE SYSTEM, Diagnostic DTC:P050031

DTC Code DTC Name
P050031 Vehicle Speed Sensor "A" No Signal

DESCRIPTION

The speed sensor detects the wheel speed and sends the appropriate signals to the skid control ECU. The skid control ECU converts these wheel speed signals into a pulse signal and outputs it to the ECM via the combination meter. The ECM determines the vehicle speed based on the frequency of this pulse signal.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory Note
P050031 Vehicle Speed Sensor "A" No Signal

1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other


  1. All of the following conditions are met:


    1. Park/neutral position switch D input signal is ON.

    2. Any of the following conditions are met:


      1. Vehicle being driven in 1st gear:

        Transmission revolution sensor (NT) value is 1450 rpm or more.

      2. Vehicle being driven in 2nd gear:

        Transmission revolution sensor (NT) value is 840 rpm or more.

      3. Vehicle being driven in 3rd gear:

        Transmission revolution sensor (NT) value is 540 rpm or more.

      4. Vehicle being driven in 4th gear:

        Transmission revolution sensor (NT) value is 400 rpm or more.

      5. Vehicle being driven in 5th gear:

        Transmission revolution sensor (NT) value is 330 rpm or more.

      6. Vehicle being driven in 6th, 7th or 8th gear:

        Transmission revolution sensor (NT) value is 300 rpm or more.

    3. The counter gear speed is 300 rpm or more.

  2. No vehicle speed signal is transmitted to the ECM.

  3. 2 seconds

  4. 1-trip detection logic


  • Open or short in vehicle speed signal circuit

  • Combination meter system

  • ECM

Comes on DTC stored

SAE Code:

P0500

MONITOR DESCRIPTION

The ECM assumes that the vehicle is being driven when the transmission counter gear indicates more than 300 rpm or more. If there is no speed signal from the combination meter despite this condition being met, the ECM interprets this as a malfunction in the speed signal circuit. The ECM then illuminates the MIL and stores the DTC.

WIRING DIAGRAM

Refer to SFI system DTC P050031.

Click here

CAUTION / NOTICE / HINT

Note

Perform registration and/or initialization when parts related to the automatic transaxle are replaced.

Click here

Tech Tips

After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.


  1. Turn the ignition switch to ON and wait for 3 seconds or more.

  2. Drive the vehicle at 19 km/h (12 mph) or more for 2 seconds or more.

  3. Check for DTCs again.

    Click here

PROCEDURE


  1. READ VALUE USING GTS (VEHICLE SPEED)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Transmission / Data List / Vehicle Speed.

    5. Drive the vehicle.

    6. In accordance with the display on the GTS, read the Data List.


      Powertrain > Transmission > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Vehicle Speed Vehicle speed

      Min.: 0 km/h (0 mph)

      Max.: 255 km/h (158 mph)

      Actual vehicle speed
      • This is the current vehicle speed.

      • The vehicle speed is detected using the wheel speed sensors.


        • Vehicle speed data is delayed when it is displayed. Therefore, even if the vehicle speed listed in the freeze frame data is 0 km/h (0 mph), this does not always mean that the malfunction occurred when the vehicle was stopped.


      Powertrain > Transmission > Data List
      Tester Display
      Vehicle Speed
      OK
      Vehicle speed displayed on the GTS and speedometer display are equal.
      Result
      Proceed to
      OK
      NG

    OK
    NG
  2. CHECK COMBINATION METER SYSTEM


    1. Check the circuits that send vehicle speed signals to this system in the meter system.

      Click here

    2. During inspection for the meter section, if there is an instruction that indicates to go back to inspections for each system, proceed to the next step.

      Result
      Proceed to
      NEXT

    NEXT
  3. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)


    1. Disconnect the F126 combination meter assembly connector.

    2. Disconnect the A43 ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      F126-5 (+S) - A43-39 (SPD) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG
    OK
  4. REPLACE ECM


    1. Replace the ECM.

      Click here

      Result
      Proceed to
      NEXT

    NEXT