Description and Operation

Description

The EPS (Electric Power Steering, electric power-assisted steering column) system uses an electric motor to assist steering effort, and this motor operates an independent steering system. The EPS control module controls motor operation according to information received from each sensor and the CAN (Controller Area Network), resulting in more accurate 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. The EPS unit assembly, steering column, and EPS unit must not be disassembled for inspection. If necessary, they should be replaced. Note: Regarding diagnostics

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 affected on one side by dropped parts. - Precision engine/control unit 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 - Incorrect weld point - 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 impacted, replace them with new ones. 2. Avoid exposing electronic parts to heat and moisture. 3. Do not touch the connection terminals to avoid deformation and static electricity. 4. Do not strike the motor and torque sensor parts. If dropped or impacted, replace them with new ones. 5. Connectors must be disconnected or connected with the ignition switched off.