Chassis, generic

C0730 Electric Power Steering Motor Position Sensor Circuit

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

Neither the publicly available J2012 lists nor NHTSA bulletins or maker indexes show C0730, so its use is not publicly verifiable. The sensor it names reports the rotor angle of the brushless assist motor, without which the module cannot commutate the phases or run field-oriented current control. Infineon places a rotary magnetic angle sensor on the motor and offers dual-die parts such as TLE5012BD and TLE5x09D so that two independent readings can be compared; NXP lists encoder or resolver processing and rotor position among the core jobs of the steering controller. A circuit fault means the angle signal is missing, shorted or electrically implausible. Without a trustworthy rotor angle the motor cannot be driven safely, so assist is withdrawn, often abruptly, and the steering turns heavy.

Likely causes

Rotor position sensor in the EPS motor defective
Poor connection between sensor and control board
Sensor magnet loose or misaligned after repair

Symptoms

  • Steering assist drops out suddenly, warning lamp on
  • Steering jerky or uneven while turning

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€300–2,500
Time1–5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

eps motor position sensoreps control module

Related codes

C0725C0735

References: community.infineon.com, nxp.com.