U0015Medium Speed CAN Communication Bus (-) Open
- Generic OBD-II code · Network
- How the car detects it
- U0015 stands for a break in CAN-Low, the (-) conductor of the medium-speed CAN. Modules separated by the break stop exchanging data with the rest of the network, whereas units still connected on both wires keep working; which functions disappear therefore depends on where the line is cut. Ford's F-Super Duty bulletin shows how a single open connector in the MS-CAN switches off the HVAC controls, the front switch panel and the headlamp function together. Common high-speed transceivers cannot diagnose a line interruption themselves (NXP), so the code results from the module's own reasoning about missing replies. No manufacturer documents U0015 publicly. Wiring that moves, such as door, tailgate and seat harnesses, and connectors opened during body or upfit work are the first places to check.
- What you may notice
- Only some comfort functions lost, depending on break location
- Fault varies when doors or seats are moved
- Likely causes
- LikelyCAN-Low conductor fractured in a moving harness section
- PossibleConnector not reconnected after body or upfit work
- RareCorroded CAN-Low splice
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.