U0046Vehicle Communication Bus C
- Generic OBD-II code · Network
- Can trigger limp mode
- How the car detects it
- U0046 covers Vehicle Communication Bus C in general, the third manufacturer-assigned network slot after Bus A and Bus B. Public uses are rare. Stellantis lists U0046-00 among the faults addressed by powertrain control module flash 18-071-26 for the 2025 Ram 1500 with the 3.0-litre Hurricane twin-turbo six; the bulletin pairs its long code list with a possible MIL but does not single out the bus fault as the reason for the lamp. Ford's 2014 Boss 302S code table names U0046 as well, without marking it as a MIL code. Behind the code there may be a wiring fault, a module that stops talking or plain software, so check for accompanying lost-communication codes first, then supply, ground and bus wiring of the modules on that network before replacing parts.
- What you may notice
- Check-engine lamp possible together with other stored codes (Ram 1500)
- Functions of modules on Bus C unavailable
- Lost-communication codes stored alongside
- Likely causes
- PossibleControl module software that misjudges the bus (Ram 1500: PCM flash)
- PossibleDamaged bus wiring or poorly seated connector on Bus C
- PossibleSupply or ground fault at a module on Bus C
- Repair
- Hard · Usually a job for a workshop.Typical cost: €50 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.