U0013Medium Speed CAN Communication Bus (+) Low
- Generic OBD-II code · Network
- How the car detects it
- U0013 indicates that CAN-High on the medium-speed bus, the (+) wire, is pulled toward ground. Where this network uses the same differential layout as high-speed CAN, as Saab's terminated mid-speed GMLAN suggests, a grounded CAN-High rules out any dominant bit; onsemi and NXP list this short among those that end all communication. Every node on the segment, usually body, climate and infotainment units, therefore goes quiet together, and the gateway or body controller stores missing-message codes for them. No manufacturer documents U0013 publicly. Powertrain functions on the separate fast bus normally carry on. With the battery off, a resistance of only a few ohms from CAN-High to ground locates the short; typical spots are door boots, seat rails and trim fasteners.
- What you may notice
- All comfort and infotainment modules fail together
- Engine and transmission keep working normally
- Likely causes
- LikelyMedium-speed CAN-High insulation damaged against body ground
- PossibleWires broken open in a door boot or tailgate grommet
- RareComfort module transceiver pulling CAN-High down
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €700
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.