P0C9C14 Volt Power Module Current Sensor B Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P0C9C flags an electrical problem, not further classified, with current sensor B of the 14 volt power module, the DC/DC converter that supplies the 12 V network from the high-voltage battery; GM calls it the accessory power module (APM). In GM's 2013 eAssist table sensor B is the APM output current sensor, while sensor A (P0A86 to P0A8A) measures the input side. No manufacturer documents P0C9C publicly; GM uses only the low and high codes P0C9E and P0C9F plus the A/B correlation code P0CC5. CARB rule (e)(15.3.1) calls for continuous range and continuity monitoring of such inputs. With no trustworthy output current the converter may be derated, and the 12 V battery can slowly discharge. The sensor normally sits inside the module.
- What you may notice
- Warning lamp, sometimes a charging-system message
- 12 V battery running low over time
- Likely causes
- LikelyCurrent sensor B inside the power module failed
- PossiblePoor contact at the power module signal connector
- RareControl software of the power module or hybrid controller
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €1,800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.