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For 1990-2009 cars only

DTC P0500 With ABS


Object Number: 896271  Size: MF

Circuit Description

Vehicles equipped with antilock brakes (ABS) receive vehicle speed from the right front wheel speed sensor. The right front wheel speed sensor produces an AC voltage of different amplitude and frequency depending on the velocity of the right front wheel. The sensor produces a readable AC voltage signal when vehicle speed is above 5 km/h (3 mph). This speed signal is sent to the electronic brake and traction control module (EBTCM), which converts the AC voltage of the sensor to a square wave. The square wave is produced by the EBTCM grounding circuit 1909, which is pulled up to 12 volts through a resistor in the engine control module (ECM). DTC P0500 sets when the ECM does not detect a square wave vehicle speed signal for a certain length of time when certain conditions have been met.

Conditions for Setting the DTC

DTC  P0500 will set is the ECM detects vehicle speed less than 20 km/h (13 mph) when:

    • The condition exists for longer than 1 second.
    • The transmission is in 4th gear.
    • The engine speed is greater than 1,800 RPM.
    • The engine coolant temperature (ECT) is greater than 40°C (104°F).
    • No CAN link DTCs have been set.

DTC P0500 diagnostic runs continuously once the above conditions have been met.

DTC P0500 is a type B DTC.

Diagnostic Aids

Important: If ABS DTC C0040, C0041, or C0245 is also set, diagnose that DTC first. If a right front wheel speed signal is not sent to the EBTCM, the EBTCM will not supply a vehicle speed signal to the ECM.

To locate an intermittent problem, use the scan tool to monitor VEHICLE SPEED in the ECM data table with the vehicle raised and drive wheels moving greater than 5 km/h (3 mph). Wiggling the wires while watching for a change in VEHICLE SPEED may locate the area where an open or short to ground in the wiring could lie.

Important: The speedometer uses the OSS sensor for vehicle speed, NOT the right front wheel speed sensor. If ECM DTC P0500 is active, the speedometer will still be operative.

Right front wheel speed sensor resistance is 1,000-2,000 ohms


Object Number: 898264  Size: FP

DTC P0500 Without ABS

Circuit Description


Object Number: 898997  Size: FP

Vehicles equipped with antilock brakes (ABS) receive vehicle speed from a right front wheel speed sensor. The right front wheel speed sensor produces an AC voltage of different amplitude and frequency depending on the velocity of the right front wheel. The sensor produces a readable AC voltage signal when vehicle speed is above 5 km/h (3 mph). This speed signal is sent to a wheel speed signal conditioner module, which converts the AC voltage of the sensor to a square wave. The square wave is produced by the conditioner module grounding circuit 1909, which is pulled up to 12 volts through a resistor in the engine control module (ECM). DTC P0500 sets when the ECM does not detect a square wave vehicle speed signal for a certain length of time when certain conditions have been met.

Conditions for Setting the DTC

DTC P0500 will set is the ECM detects vehicle speed less than 20 km/h (13 mph) when:

    • The condition exists for longer than 1 second.
    • The transmission is in 4th gear.
    • The engine speed is greater than 1,800 RPM.
    • The engine coolant temperature (ECT) is greater than 40°C (104°F).
    • No CAN link DTCs have been set in the ECM.

DTC P0500 diagnostic runs continuously once the above conditions have been met.

DTC P0500 is a type B DTC.

Diagnostic Aids

To locate an intermittent problem, use the scan tool to monitor VEHICLE SPEED in the ECM data table with the vehicle raised and the drive wheels moving greater than 5 km/h (3 mph). Wiggling the wires while watching for a change in VEHICLE SPEED may locate the area where an open or short to ground in the wiring could lie.

Important: The speedometer uses the OSS sensor for vehicle speed, NOT the right front wheel speed sensor. If ECM DTC P0500 is active, the speedometer will still be operative.

Right front wheel speed sensor resistance is 1,000-2,000 ohms


Object Number: 898503  Size: FP

Object Number: 898505  Size: FP