Powertrain, generic · Hybrid propulsion

P0C63 Drive Motor B Position Sensor Circuit B Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0C63 is reserved for short-lived dropouts or erratic jumps on Circuit B, the second winding of the motor B resolver, that do not settle into a steady fault. No manufacturer documents this code publicly. The best public illustration comes from GM's 2008 Tahoe and Yukon Hybrid: a weak crimp at the transmission pass-through connector produced intermittent starting with motor B resolver codes, though GM files them under P0C61 and the general P0A45 and P0A46 rather than an intermittent code. That case shows where to look first, crimp joints, pass-through connectors and harness sections near moving parts. Wiggle tests under live data help catch it. P0C59 is the same fault type on Circuit A of motor B.

Likely causes

Weak crimp or loose terminal in the motor B S2/S4 path, including pass-through connectors
Intermittent wire break near moving powertrain parts
Moisture or corrosion causing unstable contact

Symptoms

  • Intermittent warning lamp
  • Occasional start problems or short loss of motor B
  • Fault not present during a workshop check

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–1,500
Time1–5 h

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

Parts involved

drive motor b position sensor bwiring harnesshybrid control module

Related codes

P0C5FP0C61P0C62P0C59P0A49

References: law.cornell.edu, static.nhtsa.gov, en.wikipedia.org.