Description and Operation

Description

The EPS (Electric Power Steering, Electric Power Steering Column) system uses an electric motor to assist steering effort, and it is a steering system independent of engine operation. The EPS control module controls the motor operation according to information received from each sensor and the CAN (Controller Area Network), resulting in more precise and timely steering assist control than conventional engine-driven hydraulic systems. The EPS system components (steering angle sensor, torque sensor, safety relay, etc.) are located inside the steering column. Do not disassemble the EPS unit, steering column, or EPS control module for inspection. Replace them if necessary. Note: Regarding diagnosis

Problem Factor	Check Item	Symptom of Malfunction	Description	NOTE
Drop, Impact and Overload	Motor	Abnormal Noise	- Visible or invisible damage may occur. The steering wheel may be damaged on one side by dropped parts. Precision motor/ECU parts are sensitive to vibration and shock. Overloading may cause unexpected damage.	- Do not use a damaged EPS. - Do not overload any component.
	ECU	Circuit damage - Improper weld points - Broken printed circuit board - Damaged precision parts
	Torque Sensor	Insufficient steering effort	Overloading the INPUT shaft may cause torque sensor malfunction.	- Do not strike connecting parts (during insertion and tightening). Use the specified tool to remove the steering wheel. (Do not hammer it.) - Do not use a damaged EPS.
	Shaft	Insufficient steering wheel effort (uneven between left and right sides)		Do not use a damaged EPS.
Pull / Dent	Restrain	- Malfunction - Power supply not possible - EPS malfunction	Disconnection between the connector part and the harness	Do not overload the suspension.
Abnormal storage temperature	Engine / ECU	Abnormal steering effort due to incorrect engine/ECU operation	- Waterproof under normal conditions - Even a small amount of moisture may cause malfunction of precision motor/ECU parts.	- Maintain normal temperature and proper humidity during storage. - Avoid submersion.

1. Do not strike electronic parts. If dropped or struck, replace them with new ones. 2. Avoid exposing electronic parts to heat and moisture. 3. Do not touch connector terminals to avoid deformation and static electricity. 4. Do not strike motor and torque sensor parts. If dropped or struck, replace them with new ones. 5. Disconnect or connect the connector with the ignition switched OFF.