Powertrain, generic · Hybrid propulsion

P0C5A Drive Motor A Position Sensor Circuit B

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0C5A is the base circuit code for Circuit B, the second pickup winding of the motor A resolver; GM calls it the S2/S4 winding, set 90 degrees from the S1/S3 winding of Circuit A. The code is meant for a fault on that winding which the controller cannot class as a low or high level. No manufacturer documents this code publicly. GM checks the S2/S4 line only through P0C5C and P0C5D. If P0C5A appears on its own, the problem is limited to the second winding and its two wires; if P0C50 is stored too, a shared part such as the connector or the excitation side is more likely. P0A3F, by contrast, covers a lost angle signal without naming a winding. Expect a warning and possibly no electric drive.

Likely causes

Open wire or loose terminal in the S2/S4 (Circuit B) lines
Damaged or corroded resolver connector
Defective second pickup winding in the resolver stator

Symptoms

  • Check engine lamp with drive system warning
  • Electric drive limited or unavailable
  • Vehicle may refuse to enter ready mode

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–2,500
Time1–6 h

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

Parts involved

drive motor a position sensor bwiring harnesshybrid control module

Related codes

P0C5BP0C5CP0C5DP0C5EP0C50P0A3F

References: law.cornell.edu, gsi.ext.gm.com, en.wikipedia.org.