Engine Controls - With ABS

Wiring Diagram:

Vehicle Speed Signal (with ABS):

P0500- VEHICLE SPEED SIGNAL (WITH ABS)
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 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.

DTC PARAMETERS
DTC P0500 will set is the ECM detects vehicle speed less than 20 km/hr (13 mph) when:
^ Condition exists for longer than 1 second
^ Transmission is in 4th gear
^ Engine speed is greater than 1800 rpm
^ 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.

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 Scan tool to monitor VEHICLE SPEED in ECM data table with vehicle raised and drive wheels moving greater than 5 km/h (3 mph). Wiggling 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.

NOTE: The speedometer uses the 055 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: 1000 - 2000 ohms