Operation CHARM: Car repair manuals for everyone.

C0050

DTC C0035-C0051

Circuit Description
The wheel speed sensor produces an alternating current signal whose amplitude and frequency vary, depending on the velocity of the wheel. The electronic brake control module (EBCM) uses the frequency of the AC signal to calculate the wheel speed.

Conditions for Running the DTC

C0035, C0040, C0045, C0050
The ignition is ON.

C0036, C0041, C0046, C0051
^ Vehicle speed is over 40 km/h (25 mph).
^ The brake pedal is not pressed.
^ The antilock brake system (ABS) is not active.

Conditions for Setting the DTC

C0035, C0040, C0045, C0050
One of the following conditions exists for 0.02 seconds:
^ The DTC will set if one wheel equals 0 while the other wheel speeds are greater than 40 km/h (25 mph)
^ A short to voltage exists in the wheel speed sensor (WSS) in one of the WSS circuits.
^ An open exists in the wheel speed sensor signal circuit.
^ A short to ground - The wheel speed sensor signal circuit is shorted to ground.

C0036, C0041, C0046, C0051
All of the following conditions exists for 0.02 seconds:
^ The DTC will set if one wheel speed is less than 2.75 km/h (1.7 mph), and the other WSS are greater than 40 km/h (25 mph).
^ The brake pedal is not pressed.
^ DTC C0035, C0040, C0045, and C0050 is not set.
^ The DTC will set if there is interference on the wheel speed circuits for 20 seconds with the brake pedal applied or 5 seconds when the brake pedal is not applied.

Action Taken When the DTC Sets
If equipped, the following actions occur:
^ The EBCM disables the ABS and traction control system (TCS) for the duration of the ignition cycle.
^ A DTC malfunction will set.
^ The ABS telltale turns ON.
^ The traction control switch light emitting diode (LED) will turn OFF.

Conditions for Clearing the DTC
The condition for the DTC is no longer present.
^ Using a scan tool, clear the DTC function.
^ The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids

C0035, C0040, C0045, C0050
If the customer comments that the ABS indicator is ON only during moist environmental conditions (rain, snow, vehicle wash, etc...), inspect the wheel speed sensor wiring for signs of water intrusion. If the DTC is not current, clear all DTCs and simulate the effects of water intrusion by using the following procedure:
1. Spray the suspected area with a 5 percent saltwater solution. To create a 5-percent saltwater solution, add 2 teaspoons of salt to 354 ml. (12 oz.) of water.
2. Test drive the vehicle over various road surfaces (bumps, turns, etc...) above 40 km/h (25 mph) for at least 30 seconds.
3. If the DTC returns, replace the suspected wheel speed sensor or repair the wheel speed sensor wiring.
4. Rinse the area thoroughly when completed.

C0036, C0041, C0046, C0051
A possible cause of this DTC is electrical noise on the wheel speed sensor harness wiring. Electrical noise could result from the wheel speed sensor wires being routed to close to high energy ignition system components, such as spark plug wires.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. This step tests the wheel speed sensor for the proper resistance value.
4. This step ensures that the wheel speed sensor generates the proper voltage.

Step 1:




Steps 2-10:





DTC C0035-C0051