General Inspection
Before and after servicing the EPS system, perform the troubleshooting and test procedure as follows. Compare the system condition with normal condition in the table below and if abnormal symptom is detected, perform necessary remedy and inspection.
| Test condition | Normal condition: Motor must not supply steering assist. | ||
|---|---|---|---|
| Symptom | Possible cause | Remedy | |
| IG Off | Motor supplies steering assist. | ASP is not calibrated. | Perform the ASP calibration using a scan tool. |
| IG power supplies | Inspect the IG power supply line. | ||
| Test condition | Normal condition: Motor must not supply steering assist, Warning lamp is illuminated. | ||
|---|---|---|---|
| Symptom | Possible cause | Remedy | |
| IG On/Engine Off | Motor supplies steering assist. | ASP is not calibrated. | Perform the ASP calibration using a scan tool. |
| EMS CAN signal is not received. | Inspect the CAN line. | ||
| Warning lamp is not illuminated. | Cluster fault | Inspect the cluster and cluster harness. | |
| Test condition | Normal condition: Motor supplies steering assist, Warning lamp is not illuminated. | ||
|---|---|---|---|
| Symptom | Possible cause | Remedy | |
| IG On/Engine On | Warning lamp is illuminated and motor does not supply steering assist. | EPS (Hot at all times) and IG power supply fault | Inspect the connector and harness for EPS (Hot at all times) and IG power supply line. |
| DTC is detected by system. | Perform the self test using a scan tool and repair or replace. | ||
| Warning lamp is illuminated and motor supplies steering assist. | ASP is not calibrated. | Perform the ASP calibration using a scan tool. | |
| CAN communication between EPS and cluster is fault. | Inspect the CAN line. | ||
ASP: Absolute Steering Position
CAN: Controller Area Network
EMS: Engine Management System
CAUTION:
The following symptoms may occur during normal vehicle operation and if there is no EPS warning light illumination, the EPS system is not malfunctioning.
- After switching the ignition on, the steering wheel becomes heavier for about 2 seconds to perform EPS system diagnostics, and then returns to normal steering condition.
- When switching on or off the ignition, the EPS relay noise may occur, which is considered normal.
- If the vehicle is steered in stationary or low speed driving condition, motor noise may occur, which is considered normal.