C035

C0235 or C035

CIRCUIT DESCRIPTION
The Electronic Brake Control Module (EBCM) receives the rear wheel speed signal from the Vehicle Control Module (VCM). The rear wheel speed signal originates from the Vehicle Speed Sensor (VSS) which is connected to the VCM. When the vehicle is not moving, the VCM will have 12 VDC present on the circuit. The EBCM checks for this voltage when the vehicle is not moving.

CONDITIONS FOR SETTING THE DTC
Electronic Brake Control Module (EBCM) not seeing the correct voltage level from the VCM at startup.

ACTION TAKEN WHEN THE DTC SETS
^ The ABS indicator lamp turns on
^ The ABS disables

Diagnostic Trouble Code (DTC) C0235 is a Condition Latched DTC, which indicates that the above actions are true until the condition is cleared.

CONDITIONS FOR CLEARING THE DTC
^ Repair the conditions responsible for setting the Diagnostic Trouble Code (DTC)
^ Use the Scan Tool Clear DTCs function

DIAGNOSTIC AIDS
Before performing any diagnostics on the ABS, resolve any Vehicle Speed Sensor (VSS) Diagnostic Trouble Codes (DTC's) currently set in the Vehicle Control Module (VCM).
This DTC can be set by a faulty Electronic Brake Control Module (EBCM) or a fault in CKT 696.
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 wire breaks inside the insulation

Thoroughly check any circuitry that is 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:
2. This step uses the voltage output from the Vehicle Control Module (VCM) (gas) or Vehicle Speed Sensor Buffer (diesel) to check the 1827 CKT.
3. This step checks the CKT 1827 for proper resistance.
5. This step checks for a short in the wiring between the Electronic Brake Control Module (ECBM) and the Powertrain Control Module (PCM).