Chassis, generic

C0745 Electric Power Steering Overtemperature Protection

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

Public documentation of C0745 is missing; it is not in the publicly available J2012 tables, in NHTSA bulletins or in maker indexes. GM reports an overheated EPS controller as C0176 (PIT5213B). The protection itself is well described in a Delphi patent: instead of relying on thermistors, the controller squares the motor current and runs it through several low-pass filters, each standing for one thermal time constant, the slowest close to 2,000 s. When a filter exceeds its limit, motor current is reduced step by step, more strictly when the motor is stalled against a lock. The example motor handles 15 A continuously or 75 A for about 5 s. Long parking manoeuvres or holding full lock therefore make the steering heavier until the unit cools down.

Likely causes

Long parking manoeuvres or holding the wheel at full lock
Stiff steering gear, joints or tyres raising motor load
Temperature estimate or sensor in the module faulty

Symptoms

  • Steering gradually heavier after repeated manoeuvring
  • Power steering warning message

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–1,500
Time0.3–4 h

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

Parts involved

eps motoreps control module

Related codes

C062AC0725C0735

References: static.nhtsa.gov, patents.google.com, nxp.com.