C0450
DTC C0450Test 1-3:
Test 4-14:
Circuit Description
The variable effort steering (VES) system uses the electronic brake control module (EBCM) to control current to a bi-directional electromagnetic rotary actuator. The EBCM commands current from negative 3 amps to positive 3 amps to the actuator. At low speeds, less than approximately 24 km/h (15 mph), negative three amps of current is commanded, providing maximum assist to steering. As speed increases, increased (more positive) current is commanded, reaching zero amps at approximately 96 km/h (60 mph). The EBCM commands positive current only during steering input at higher speeds, based on the above inputs and the vehicle calibration, which creates steering resistance.
Conditions for running the DTC
^ Ignition voltage between 10.5 - 17 volts
^ Off state test - Initial ignition ON, no engine RPM or vehicle speed present.
^ On state test - If off state test passes, engine RPM and vehicle speed present.
Conditions for Setting the DTC
An open, short to ground, or short to voltage in the VES actuator or the circuits to the actuator.
Action Taken When the DTC Sets
^ A DTC CC1450 is stored in memory.
^ The DIC may display the SERVICE STEERING SYS warning message.
^ The VES system is disabled.
Conditions for Clearing the DTC
^ A current DTC will clear when malfunction is no longer present.
^ A history DTC will clear after 100 consecutive ignition cycles with no malfunction present.
^ Using the scan tool.
Diagnostic Aids
The vehicle needs to be driven to view full commanded and feedback current ranges on the scan tool.
Test Description
The numbers refer to the step numbers on the diagnostic table.
2. Tests if the Commanded and Feedback Current parameters are at the specified value in their active state.
3. Tests if the resistance of the VES actuator is in the specified range.
7. Tests the high effort control circuit for an open or short to voltage.
8. Tests the low effort control circuit for a short to ground.
10. Tests for poor connections at the VES actuator harness connector.
13. Perform the setup procedure after EBCM replacement.