Powertrain, generic · Hybrid propulsion

P0C17 Drive Motor A Position Sensor Not Learned

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0C17 means the controller has no valid learned offset for the resolver of motor A, which it needs to align rotor position with the stator field. GM runs the learn at key-off and sets the code if it fails without a stored value: motor speed above 50 rpm, DC voltage below 192 V (200 V on the 2016 Volt), phase current below 15 A or a learn time over 1.4 s. The Volt is Type A, the 2012 two-mode trucks Type B. GM bulletin 21-NA-218 links it to missing high voltage or three-phase current, loose phase terminals or stator damage on Volt and ELR. Mazda requires the speed sensor learn on CX-90 and CX-70 PHEV after inverter or motor replacement. P0C4E reports a learned value out of range.

Likely causes

Offset learn not performed after replacing the inverter, motor or resolver
High voltage not reaching the inverter during the learn, e.g. contactor or HV cable fault
Loose three-phase ring terminals after a repair
Damaged motor stator winding (GM 21-NA-218)

Symptoms

  • Engine starts and stalls or will not start after a repair
  • Malfunction indicator lamp with reduced propulsion message
  • Electric drive unavailable

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€80–4,000
Time0.5–8 h

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

Parts involved

drive motor a position sensorhybrid control module

Related codes

P0C18P0C4EP0A3FP0A40P0C01

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com, static.nhtsa.gov.