U0016Medium Speed CAN Communication Bus (-) Low
- Generic OBD-II code · Network
- How the car detects it
- U0016 reports CAN-Low of the medium-speed bus, the (-) wire, sitting below its valid range, typically through a short to ground. Transferred from the high-speed physical layer, which Saab's two-wire terminated mid-speed GMLAN resembles, this is a fault the bus tolerates: onsemi measured continuing transmission with deformed levels, and NXP files it as a hidden failure visible only to transceivers with diagnosis. The comfort network therefore usually keeps working, but becomes more sensitive to interference; drivers rarely notice anything beyond sporadic glitches. No manufacturer documents U0016 publicly. Because the fault hides so well, the code itself is often the only clue; measure CAN-Low against ground with the battery disconnected and follow the harness near sharp edges.
- What you may notice
- Usually no lasting malfunction, code found during a scan
- Sporadic glitches in comfort functions
- Likely causes
- LikelyMedium-speed CAN-Low chafed against a ground point or sheet edge
- PossibleWater ingress in a footwell or door connector
- RareComfort module transceiver internally shorted on CAN-Low
- 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.