Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC C0450 01: Steering Assist Control Solenoid Circuit Short to BatteryDTC C0450 02: Steering Assist Control Solenoid Circuit Short to Ground
DTC C0450 04: Steering Assist Control Solenoid Circuit Open Circuit
DTC C0450 0B: Steering Assist Control Solenoid Circuit Current Above Threshold
DTC C0450 54: Steering Assist Control Solenoid Circuit Temperature High
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
VES Actuator High Control | C0450 02, C0450 0B | C0450 04 | C0450 01 | -- |
VES Actuator Low Control | C0450 02 | C0450 04 | C0450 01 | -- |
Circuit/System Description
The electronic brake control module (EBCM) commands current from 0-1A to the variable effort steering (VES) actuator, depending on vehicle speed. At low speeds, 1A of current is commanded to the actuator and the actuator valve is fully closed. A speed increases, less current is commanded to the actuator and the valve opens, allowing pressure to bleed off through a power steering fluid orifice. The EBCM monitors and compares the VES Actuator Commanded and VES Actuator Feedback Signal parameters to detect malfunctions in the VES system.
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
The EBCM detects an open, short to ground, or short to voltage in the VES actuator or the actuator circuits.
Action Taken When the DTC Sets
| • | The driver information center (DIC) displays the SERVICE STEERING SYS warning message. |
| • | The VES system is disabled for the remainder of the ignition cycle. |
Conditions for Clearing the DTC
| • | The condition for setting the DTC is no longer present. |
| • | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Variable Effort Steering System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the VES actuator.
- Ignition ON for 10 seconds, test for 5.0-7.0 volts between the low control circuit terminal 2 and ground.
- Test for B+ between the high control circuit terminal 1 and ground.
- If all circuits test normal, test or replace the VES actuator.
| ⇒ | If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the EBCM. |
| ⇒ | If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the EBCM. |
| ⇒ | If not the specified value, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the EBCM. |
Component Testing
- Ignition OFF, disconnect the VES actuator harness connector.
- Measure for 5-10 ohms between the VES actuator terminals 1 and 2.
- Measure for infinite resistance between each VES actuator terminal and the VES actuator housing.
| ⇒ | If the resistance is outside the specified range, replace the VES actuator. |
| ⇒ | If less than the specified range, replace the VES actuator. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for EBCM replacement, setup, and programming |
