C0236

Circuit Description
The EBCM receives the rear wheel speed signal from the Powertrain Control Module (PCM) (2.2L). The rear wheel speed signal originates from the Vehicle Speed Sensor (VSS) which is connected to the PCM. When the vehicle is not moving, the PCM will have 12 VDC present on the circuit. The EBCM checks for this voltage when the vehicle is not moving. Once the vehicle is moving, the EBCM checks for a missing vehicle speed sensor signal.

Conditions for Running the DTC
- Ignition switch in the RUN position.
- The vehicle is at a speed greater than 13 km/h (8 mph).

Conditions for Setting the DTC
EBCM losing the rear wheel speed signal for at least 5 seconds due to:
- Low sensor output voltage
- Vehicle speed sensor signal shorted to ground.
- Vehicle speed sensor signal shorted to 5 VDC or 12 VDC.
- Vehicle speed sensor signal processing inside EBCM interrupted.

Action Taken When the DTC Sets
- The ABS indicator lamp turns on
- The ABS disables
Malfunction responses to DTC C0236 vary, depending on the affected subsystem.
- ABS-Condition latched
- DRP-DRP critical
For a detailed explanation of DTC malfunction responses, refer to: Self-Diagnostics.

Conditions for Clearing the DTC
- Repair the conditions responsible for setting the DTC.
- Use the Clear DTCs function on the Scan Tool
- A Condition Latched DTC may exist momentarily, or constantly. In either case, the DTC will be stored in the EBCM memory until it is repaired, and/or the DTC is cleared. After the DTC is repaired and/or cleared and the ignition is turned to ON, 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 PCM first.
This DTC can be set by a faulty EBCM or VSS, or by a fault in CKT 821, 822 or 1827.
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
If the customer says that the ABS indicator lamp is on only during humid conditions such as rain, snow, or vehicle wash, then thoroughly inspect the suspected circuits for signs of water intrusion. Use the following procedure:
1. Spray the suspected area with a 5% salt water solution (two teaspoons of salt to 12 oz. of water).
2. Drive the vehicle above 24 km/h (15 mph) for at least 30 seconds.
If the DTC returns, replace the suspected harness.

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

Step 1:

Steps 2-6:

Steps 7-9:

Diagnostic Chart