An operating motor is used to support the driving force of steering wheel when the wheel is turned(rotated) by the driver. The operating motor (a brush type DC motor) is installed in middle of steering column and operates the steering column. The EPS motor can be damaged during disassembly or removal of the operating motor, so you must disassemble or remove the EPS motor with the assembly.
This DTC code refers to open/shorts in motor power circuit. This code is set if voltage monitored at two terminal of EPS CM is too high or low when EPS motor is not operated at normal motor power.
Item
Detecting Condition
Possible cause
DTC strategy
Voltage check
Open/short in power circuit
Open/short in ground circuit
Contact resistance in connections.
Faulty EPS CM
Enable conditions
Motor malfunction & relay voltage = 5.5 V
Threshold value
Motor end voltage = 8.5 V or = 0.2 V
Diagnosis time
0.5 sec
fail safe
Motor : OFF
Relay : OFF
Fail lamp : ON
Restoration condition : Power "OFF"
Fig.1) Signal waveform of (+)side terminal when turning steering wheel
Fig.2) Signal waveform of (-) side terminal when turning steering wheel
The polarity of EPS motor is alternated as direction of steering wheel when driver rotate the steering wheel to right side or left. Therefore rotate the steering wheel to right side or left and then confirm the waveform that the polarity is alternated as direction of steering wheel at the terminal "1","2".