C1001-49

C1001-49-EPS - INTERNAL ELECTRONIC FAILURE

For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Electronic Power Steering (EPS) system employs a column-mounted electric power steering unit along with a manual steering rack and pinion to provide a variable power-assisted steering with reduced parasitic engine load. The EPS controller monitors two steering wheel position sensors to determine the absolute position of the steering shaft and determines driver input via a steering wheel torque sensor. In addition, the EPS controller uses four hall-effect position sensors to monitor the absolute and commanded position of the motor. The EPS controller obtains vehicle speed, alternator output, and steering mode information, and broadcasts warning lamp status and service diagnostic information, on CAN C. During normal driving, as the driver turns the wheel, the torque sensor value changes based on the effort the driver uses to turn the wheel. The controller uses this information, along with the steering wheel absolute position and vehicle speed, to determine the amount torque required from the motor. Voltage is then provided to the motor to provide power steering assist.

- When Monitored:
Continuously.

- Set Condition:
If the Electronic Power Steering (EPS) Module detects an internal fault, this DTC will set. Most of internal faults that can set this DTC will result in the EPS assist not operating for the remainder of the current key cycle.





ACTIVE DTC

NOTE: This DTC must be active for the results of this test to be valid.

1. Ignition on, engine not running.
2. With the scan tool, record and erase DTCs.
3. Start the engine and run for two minutes.
4. With the scan tool, read DTCs.

Does the scan tool display: C1001-49-EPS - INTERNAL ELECTRONIC FAILURE?

Yes

- Replace the Electronic Power Steering (EPS) Assembly. Steering Column - Removal.
- Perform the EPS VERIFICATION TEST. EPS Verification Test.

No

- The conditions that caused this code to set are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring harness and electrical connectors.
- Perform the EPS VERIFICATION TEST. EPS Verification Test.