P0C63Drive Motor B Position Sensor Circuit B Intermittent/Erratic
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- 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.
- What you may notice
- Intermittent warning lamp
- Occasional start problems or short loss of motor B
- Fault not present during a workshop check
- Likely causes
- LikelyWeak crimp or loose terminal in the motor B S2/S4 path, including pass-through connectors
- PossibleIntermittent wire break near moving powertrain parts
- RareMoisture or corrosion causing unstable contact
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €80 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.