The electronic brake control module (EBCM) commands current from 0 to 5A to the variable effort steering (VES) actuator, depending on vehicle speed. At low speeds, 0-amps of current is commanded to the actuator and the steering gear receives full flow of power steering fluid causing less effort to steer vehicle. As vehicle speed increases, the amount of amps increases to the actuator causing fluid to bypass steering gear. This limits hydraulic assist to steering gear causing firm steering. The EBCM monitors and compares the VES Commanded Current and VES Feedback Current parameters to detect malfunctions in the VES System.

An open, short to ground, or short to voltage in the VES actuator or the circuits to the actuator.

Schematic Reference

Power Steering Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Important: It is recommended that Component Testing is performed before Circuit/System Testing when diagnosing the VES actuator because the module will default and does not supply voltage to the sensor when the DTC is set.

1. Ignition OFF, disconnect the harness connector at the VES actuator.

Important: In order to ensure correct test results, the J-35616 test lamp must be used to perform the following steps. Failure to use the J-35616 test lamp may result in inaccurate test results and potential misdiagnosis.

2. Ignition ON, verify that a test lamp illuminates between the control circuit terminal A and ground.

⇒	If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance.

3. Ignition OFF, connect the test lamp between the control circuit terminal A and the control circuit terminal B.
4. Ignition ON, verify the test lamp briefly illuminates for approximately 1 second, then turns OFF.

⇒	If the test lamp is always ON, test the control circuit terminal B for a short to ground. If the circuit tests normal, replace the EBCM.

⇒	If the test lamp is always OFF, test the control circuit terminal B for a short to voltage or an open/high resistance. If the circuit tests normal, replace the EBCM.

5. If all circuits test normal, test or replace the VES actuator.

1. Ignition OFF, disconnect the VES actuator harness connector terminal A and B.
2. Measure for 2.5-10 ohms of resistance between the VES actuator terminals.

⇒	If not 2.5-10 ohms of resistance, replace the VES actuator.

3. Measure for infinite ohms of resistance between each VES actuator terminals and the VES actuator housing.

⇒	If less than the specified range, replace the VES actuator.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.