Circuit Description
The EBCM controls a bi-directional magnetic rotary solenoid. The solenoid is in the steering gear. The solenoid adjusts the amount of power steering assist in order to achieve a given level of driver effort in turning the vehicle. The EBCM varies the steering assist by adjusting the current flow through the solenoid. The amount of steering assist adjusted for steering is dependent upon vehicle speed. As the vehicle speed increases, the following actions occur:
| • | The steering assist decreases. |
| • | The driver effort increases. |
As the vehicle speed decreases, the following actions occur:
| • | The steering assist increases. |
| • | The driver effort decreases. |
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The EBCM detects an open or short in the VES circuit when the feedback current is less than 360 mA while the absolute value of the commanded current is greater than 826 mA for 2.5 seconds.
Action Taken When the DTC Sets
| • | The EBCM disables the variable effort steering (VES) for the duration of the ignition cycle. |
| • | The DIC displays the SERVICE STEERING SYS message. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present (the DTC is not current) and you used the scan tool Clear DTC function. |
| • | The condition for the DTC is no longer present (the DTC is not current) and you used the On-Board Diagnostics Clear DTC function. |
| • | The EBCM automatically clears the history DTC when a current DTC is not detected in 50 consecutive drive cycles. |
Diagnostic Aids
The vehicle may need to be driven to view non-zero values of the MagnaSteer® Commanded Current and MagnaSteer® Feedback Current on the scan tool.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step uses the scan tool to check the Magna Steer Feedback Current parameter.
-
This step checks for an open in the variable effort steering actuator and circuit.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Variable Effort Steering Diagnostic System Check? | -- | Go to Step 2 | |||||||
Does the scan tool indicate that the Magna Steer Feedback Current is greater than the specified value? | 360 mA | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 | |||||||
3 |
Does the resistance measure within the specified range? | 1.6-3.1 ohms | Go to Step 5 | Go to Step 4 | ||||||
4 | Test both variable effort steering control circuits for a high resistance or an open between the variable effort steering actuator pigtail connector and the variable effort steering actuator. Refer to Circuit Testing and Wiring Repairs in Wiring System. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 8 | ||||||
5 | Test both variable effort steering control circuits for a short between the variable effort steering actuator pigtail connector and the variable effort steering actuator housing. Refer to Circuit Testing and Wiring Repairs in Wiring System. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 6 | ||||||
Does the resistance measure within the specified range? | 1.6-5 ohms | Go to Step 7 | Go to Step 9 | |||||||
7 | Test both variable effort steering control circuits for a short to ground or short to voltage between the EBCM and the variable effort steering actuator pigtail connector. Refer to Circuit Testing and Wiring Repairs in Wiring System. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 12 | ||||||
8 | Inspect for poor connections at the harness connector of the variable effort steering actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 11 | ||||||
9 | Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 10 | ||||||
10 | Test for and repair one of the following conditions in the suspect variable effort steering control circuit between the EBCM and the variable effort steering actuator pigtail connector.
Refer to Wiring Repairs in Wiring System. Did you complete the repair? | -- | Go to Step 13 | -- | ||||||
11 | Replace the variable effort steering actuator. Refer to Steering Gear Replacement in Power Steering System. Did you complete the repair? | -- | Go to Step 13 | -- | ||||||
12 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement in Antilock Brake System. Did you complete the repair? | -- | Go to Step 13 | -- | ||||||
13 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
