2000 C5,

I am getting the RF speed sensor code for open or shorted. How I can I verify if the speed sensor is bad or not ?

 

I found what I was looking for. Credit goes to GrandpasC502. Originally posted by Bill Dearborn. I have pasted it below for others that may need to know how to do this.

Thanks Grandpa for reposting this so I could find it..


Here is the content of a post by forum member Bill Dearborn.


C1232 indicates there is a potential problem with the left front Wheel Speed Sensor.

Here are the diagnostic procedures you can follow to see if you can fix it. I deleted the ones that required a Tech 2.

DTC C1232-C1235

Circuit Description
As the wheel spins, the wheel speed sensor produces an AC signal. The electronic brake control module (EBCM) uses the frequency of the AC signal to calculate the wheel speed.

Conditions for Running the DTC
C1232 through C1235
The ignition is ON.

Conditions for Setting the DTC
C1232 through C1235
One of the following conditions exists for 0.02 seconds:
• A short to voltage - the wheel speed sensor signal circuit and wheel speed sensor return circuit voltages are both greater than 4.25 volts.
• A short to ground - the wheel speed sensor signal circuit and wheel speed sensor return circuit voltages are both less than 0.75 volts.
• An open - the wheel speed sensor signal circuit voltage is greater than 4.25 volts and wheel speed sensor return circuit voltage is less than 0.75 volts.

Action Taken When the DTC Sets
If equipped, the following actions occur:
• The EBCM disables the ABS/TCS/VSES for the duration of the ignition cycle.
• The DRP does not function optimally.
• The ABS indicator turns ON.
• The Traction Control and Active Handling indicator turns ON.
• The DIC displays the following messages:
o Service ABS
o Service Traction System
o Service Active Handling

Conditions for Clearing the DTC
• The condition for the DTC is no longer present and the DTC is cleared with a scan tool.
• The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids
C1232 through C1235
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 (9.9 ml) 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.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step 3. Measure the resistance of the wheel speed sensor in order to determine if the sensor has a valid resistance value.
Step 5. Ensures that the wheel speed sensor is generating a valid AC voltage output.
Step Action Values Yes No

Step 3
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Disconnect the wheel speed sensor connector.
3. Measure the resistance across the wheel speed sensor.
4. Does the resistance measure within the specified range? 850-1350 ohms Go to Step 4
Go to Step 8

Step 4
1. Spin the wheel.
2. Measure the AC voltage across the wheel speed sensor.
3. Does the AC voltage measure greater than the specified value? 100 mV Go to Step 5
Go to Step 8

Step 5
1. Inspect for poor connections at the harness connector of the wheel speed sensor. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
2. Did you find and correct the condition? -- Go to Step 10
Go to Step 6

Step 6
1. Disconnect the EBCM harness connector.
2. Install the J 39700 universal pinout box using the J 39700-300 cable adapter to the EBCM harness connector only.
3. Test the wheel speed sensor circuits for the following:
o An open
o A short to ground
o A short to voltage
o Shorted together
Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
4. Did you find and correct the condition? -- Go to Step 10
Go to Step 7