C0235

Circuit Description
The EBCM receives the rear wheel speed signal from the VCM/PCM. The rear wheel speed signal originates from the Vehicle Speed Sensor (VSS) which is connected to the VCM/PCM. When the vehicle is not moving, the VCM/PCM will have 12 VDC present on the circuit. The EBCM checks for this voltage when the vehicle is not moving.

Conditions for Running the DTC
The ignition switch is in the RUN position.

Conditions for Setting the DTC
The EBCM does not see the correct voltage level from the VCM/PCM at start-up.

Action Taken When the DTC Sets
^ The ABS indicator lamp turns on.
^ The ABS disables.
DTC C0235 is a Condition Latched DTC, which indicates that the above actions are true until the condition is cleared.
DTC C0235 is a DRP critical DTC, which means that DRP is disabled and the BRAKE indicator lamp will also light.

Conditions for Clearing the DTC
^ Repair the conditions responsible for setting the DTC.
^ Use the Scan Tool Clear DTCs function.
^ A Condition Latched DTC may exist momentarily, or constantly. In either case, the DTC will be stored in the EBCM memory until the DTC is repaired and/or cleared. After the DTC is repaired and/or cleared and the ignition switch is turned to the ON position, the ABS lamp will remain lit until the EBCM completes a power-up self test. This test concludes when the vehicle has reached a speed of greater than 13 km/h (8 mph) and the wheel speed inputs have been checked by the EBCM.

Diagnostic Aids
Check for and clear DTCs in the VCM/PCM first. This DTC can be set by a faulty EBCM or a fault in CKT 18 27.
If the voltage readings are low or varying, the battery or charging system could be the cause. Check these areas before replacing any components. In addition, any of the following conditions may cause an intermittent malfunction:
^ A poor connection
^ Wire insulation that is rubbed through
^ A broken wire inside the insulation
Thoroughly check any circuitry suspected of causing the intermittent complaint for the following conditions:
^ Backed out terminals
^ Improper mating
^ Broken locks
^ Improperly formed or damaged terminals
^ Poor terminal to wiring connections
^ Physical damage to the wiring harness

Test Description
The numbers below refer to the steps in the diagnostic table:
3. This step uses the voltage output from the PCM/VCM to check the 1827 CKT.
4. This step attempts to determine if there the VCM/PCM can process the VSS input and deliver a VSS output on CKT 1827.