U3015Control Module Ground C
- Generic OBD-II code · Network
- Can trigger limp mode
- How the car detects it
- U3015 reports that the third ground path of a module, labelled C, is missing or no longer plausible. Three or four separate grounds are found mainly on units that drive heavy loads, such as brake, steering or power distribution modules, where control electronics and power stages return current through their own wires. No manufacturer documents U3015 publicly. The published logic for grounds A and B gives the pattern: GM's 19OBDG03B brake module compares the voltages on two grounds and flags one as lost once the ratio leaves ±0.9, and Ford's 26-2150 ties each ground letter to a specific body point. Which pin is C is defined only by that module's wiring diagram. A failing ground C can bring warning lamps, a disabled function or erratic readings from the same module.
- What you may notice
- Warning lamp or message for the system run by the affected module
- Function cut back or switched off, often depending on load or moisture
- Stored together with other supply or ground codes of the same module
- Likely causes
- LikelyCorroded or loose ground eyelet at the body or frame point
- PossibleChafed or broken ground wire between module and ground point
- PossibleSpread or corroded ground pin in the module connector
- RareInternal fault in the module's ground measurement
- Repair
- Medium · Often possible to do yourself.Typical cost: €10 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.