[rshadd]

C0222 Missing Right Front Speed Signal

Probable Cause

Open or short circuit condition
Poor electrical connection
Faulty wheel speed sensor
Faulty EBCM

 

[rshadd]

The thing to do, is follow the wiring back to the EBCM. Disconnect it there, and connect an ohmmeter to the sensor side of the wiring. If you get a reading other than infinite resistance, wiggle the wiring with the ohmmeter still hooked up, and see if it goes open. If you get an open reading right away, go to the shorter sensor lead, and check again there. If that reads continuity, there is a break in the secondary lead. If you get continuity at all times, switch to an AC volt meter at the sensor side of the lead at the EBCM. While spinning the wheel fairly quickly by hand, you should get a reading of about 1/2 volt.

If you do, there may be a problem with the EBCM, or with the connection there. If you do not read AC voltage while spinning the wheel. you may have a 2nd faulty wheel speed sensor, or a sensor that's not properly seated, or some sort of debris between it and the Tone Exciter Ring. The gap between the sensor and ring has to be very precise. Any rust buildup or such on the mounting can hold the sensor too far away, preventing a sufficient voltage from being generated. Likewise, rust debris in the teeth of the ring or sticking to the sensor can prevent a voltage from being generated. or make it very weak.

 

[rshadd]

Correct. On the 04-06 models, the wheel hub and speed sensor are serviced as an assembly.

Odds are, you just have some rust suck to the magnet.

 

[rshadd]

DTC C0220-C0229

Circuit Description

The electronic brake control module (EBCM) energizes the appropriate isolation and dump valve solenoids to control hydraulic pressure applied to a brake circuit during and Antilock Brake System (ABS) event.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

• DTC C0220 Left Front ABS Channel in Release Too Long
• DTC C0221 Right Front ABS Channel in Release Too Long
• DTC C0222 Rear Antilock Brake System (ABS) Channel in Release Too Long

Conditions for Running the DTC

• The ignition is ON
• The vehicle is experiencing an ABS event

Conditions for Setting the DTC

An ABS event lasting 36 seconds or longer occurs on any brake circuit.

Action Taken When the DTC Sets

The EBCM disables the ABS/TCS/dynamic rear proportion (DRP).
The ABS indicator turns ON.
The brake warning indicator turns ON.
The ABS fault message is displayed.
The brakes message is displayed.

Conditions for Clearing the DTC

The conditions for setting the DTC are no longer present and you use the scan tool Clear DTCs function.

Diagnostic Aids

Always diagnose and repair any wheel speed sensor failures prior to diagnosing DTC C0220, C0221 or C0222.

These DTCs may set, theoretically, when the ABS is activated on surfaces that are nearly impossible to get traction on. If the DTC sets within these conditions, diagnosis of the ABS system is not necessary.

Test Description

The number below refers to the step number on the diagnostic table:

2: Performing solenoid test determine if there is a mechanical malfunction inside the brake pressure modulator valve (BPMV).​

DTC C0220-C0229
0AsHYiZ0vsVKtdFJJWUV6MTF4XzlzQ2JfSUxWNk82MlE

 

[rshadd]

Sounds like you're on to something. What a relief. I never knew the trucks without rear ABS calculated rear wheel speed.