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 C0545 00: Steering Wheel Torque Input SensorDTC C0545 4B: Steering Wheel Torque Input Sensor Calibration Not Learned
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
EPS B+ | U2143 00, U211 00,* | U2143 00, U211 00,* | -- | -- |
EPS Ignition | U2143 00, U211 00,* | U2143 00, U211 00,* | -- | -- |
5-V Reference | C0545 00 | C0545 00 | -- | -- |
Steering Position Sensor Signal | C0460 00 | C0460 00 | C0460 00 | C0460 00 |
Steering Position Sensor Signal | C0460 00 | C0460 00 | C0460 00 | C0460 00 |
Torque Sensor Signal | C0545 00 | C0545 00 | C0545 00 | C0545 00 |
Torque Sensor Signal | C0545 00 | C0545 00 | C0545 00 | C0545 00 |
Low Reference | C0545 00 | C0545 00 | -- | -- |
PSCM Ground | -- | U2143 00, U211 00,* | -- | -- |
* No communication with PSCM | ||||
Circuit/System Description
The steering column shaft torque sensor is a 5-volt dual analog inverse signal device which is used to sense steering direction and the amount of torque being applied to the steering column shaft when the steering wheel is turned. The valid signal voltage range of the sensor is 0.25-4.75 volts. When applying torque to the steering column shaft during a right turn, the sensors signal 1 voltage increases, while the signal 2 voltage decreases within the valid signal voltage range. When applying torque to the steering column shaft during a left turn, the sensors signal 1 voltage decreases, while the signal 2 voltage increases within the valid signal voltage range.
After replacing the steering column or power steering control module (PSCM), the steering wheel torque and position sensors must be calibrated.
Conditions for Running the DTC
C0545 00
| • | Engine running |
| • | Steering column shaft torque input is present. |
C0545 4B
The ignition is ON.
Conditions for Setting the DTC
C0545 00
The torque sensors signal 1 and signal 2 voltages are less than 0.25 volts, or greater than 4.75 volts.
C0545 4B
The PSCM has not undergone the torque sensor calibration procedure.
Action Taken When the DTC Sets
| • | DTC is stored in memory. |
| • | The DIC displays the POWER STEERING warning message. |
| • | No steering assist is provided. |
Conditions for Clearing the DTC
C0545 00, C0545 4B
| • | A current DTC will clear on the next malfunction-free ignition cycle. |
| • | A history DTC will clear after 100 consecutive malfunction-free ignition cycles. |
Diagnostic Aids
If the PSCM continues to set a history DTC C0545 replace the steering column before replacing the PSCM. Some steering columns may have an intermittent internal wiring condition causing the history DTC C0545.
If the Steering torque or position sensor calibrations are incorrect the customer may complain of steering effort that is easier in one direction than the other. Performing the steering torque and position sensor calibrations procedure will correct this issue.
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Power Steering System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Special Tools
EL-47564 Power Steering Control Module (PSCM) Test Harness
Circuit/System Verification
C0545 00
Ignition ON, observe the scan tool Torque Sensor Signal 1 and 2 parameters. With the steering wheel at rest both readings should be at 2.5 V. While turning the steering wheel from side to side the readings should stay between 0.25-4.75 V and change in opposite directions of each other.
C0545 4B
Verify that DTC C0545 4B is not set.
| ⇒ | If the DTC is set, perform the Torque Sensor Calibration procedure. If the DTC resets, replace the PSCM. |
Steering torque and position sensor calibrations
- Center the steering wheel.
- Using the scan tool Perform the Steering Position Sensor Calibration procedure.
- Using the scan tool Perform the Torque Sensor Calibration procedure.
- Turn the steering wheel until it stops in each direction.
Important: After centering the steering wheel, remove hands and other objects from the steering wheel and ensure the suspension is relaxed and no bias, or uneven force is being applied to the steering system.
Circuit/System Testing
C0545 00
- Disconnect the X3 harness connector at the power steering module assembly.
- Connect the EL-47564 Power Steering Control Module (PSCM) Test Harness.
- Ignition OFF, test for less than 2 Ω between the low reference circuit terminal E and ground.
- Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal B and ground.
- Install a 3A fused jumper wire between the signal circuit terminal F and the 5V reference circuit terminal B. Verify the scan tool Torque Sensor Signal 1 is greater than 4.8V.
- Install a 3A fused jumper wire between the signal circuit terminal C and the 5V reference circuit terminal B. Verify the scan tool Torque Sensor Signal 2 is greater than 4.8V.
- If all circuits test normal, test or replace the steering column.
| ⇒ | If greater than the specified range, replace the power steering control module. |
| ⇒ | If less than the specified range, replace the power steering control module. |
| ⇒ | If less than the specified value, replace the power steering control module. |
| ⇒ | If less than the specified value, replace the power steering control module. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for PSCM replacement, setup, and programming |
