EPS CM (MDPS=Motor Driving Power Steering) measures operating torque using torque sensor when driver operates steering wheel. The EPS CM controls the current of EPS motor in proportion to vehicle speed and operating torque of steering wheel. EPS CM, at times, supplies or cuts off current (as determined by engine control relay fail safe relay inside EPS CM) to EPS motor operating source and system source.
This DTC code is about failure of fail safe relay. While monitoring relay contact voltage, if motor source is supplied continuously, even with IG key OFF, EPS CM regards this as stuck relay inside EPS CM (MDPS=Motor Driving Power Steering) and then sets this code.
Item
Detecting Condition
Possible cause
DTC Strategy
Voltage check
Sticky fail-safe relay contact part
Enable conditions
Fail-safe relay "OFF"( just once at IG"ON")
Voltage between motor terminal < 5V
Threshold value
Fail-safe relay contact voltage = 9.0 V
Diagnosis time
5 sec
Fail safe
Motor : OFF
Relay : OFF
Fail lamp : ON
Restoration condition : Power "OFF"