U0019Low Speed CAN Communication Bus
- Generic OBD-II code · Network
- How the car detects it
- U0019 is the general fault slot for the low-speed CAN, the slow body network serving doors, lighting, locks and comfort electronics. Two physical forms exist: the two-wire fault-tolerant CAN of ISO 11898-3, which NXP's TJA1055 runs at up to 125 kBd and keeps alive on one wire after a single break or short, and the one-conductor low-speed GMLAN that GM runs at 33.33 kbit/s. FCA names U0019 CAN B Bus; on the 2015 Ram ProMaster the BCM logged U0019-01 (general electrical failure) with a lit MIL, cured by a BCM reflash under bulletin 08-230-22. Mercedes-Benz lists U001988 among the codes behind false anti-theft alarms in 2019-25 models and has supply, ground and CAN lines to the overhead panel checked. Comfort functions suffer rather than driveability.
- What you may notice
- Comfort functions such as locks, lighting or windows fail or act erratically
- Anti-theft alarm triggers without obvious reason
- Lost-communication codes for several body modules
- MIL on in some vehicles (FCA ProMaster 2015)
- Likely causes
- LikelyDamaged low-speed bus wiring or corroded, loose connector pins
- PossiblePoor supply or ground at a module on the body bus
- PossibleModule software logging the code without a real fault (FCA ProMaster BCM)
- RareFaulty module or transceiver disturbing the low-speed bus
- Repair
- Hard · Usually a job for a workshop.Typical cost: €60 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.