U0088Vehicle Communication Bus F (-) Shorted to Bus F (+)
- Generic OBD-II code · Network
- Can trigger limp mode
- How the car detects it
- With U0088 the two conductors of Vehicle Communication Bus F are bridged to each other. Signalling on both FlexRay and CAN rests on the difference between the wires, so with them joined there is none: a FlexRay receiver such as NXP's TJA1081B sees a difference below its activity threshold and treats the line as idle, while every sending node reads back something other than what it transmits and sets its bus error flag. On a single channel this ends all exchange on Bus F, which is why modules elsewhere then log the silent partners as lost. Volvo names a short between CAN-High and CAN-Low as one cause of U008088 on its truck datalink 7. For CAN, onsemi's bench tests likewise show a bridged pair stopping all traffic. Isolate sections by unplugging connectors while measuring between the wires.
- What you may notice
- Complete loss of the functions served by Bus F
- Lost-communication codes for several modules
- Likely causes
- LikelyBus F pair crushed so both wires touch
- PossibleWater or corrosion bridging both wires in a splice or connector
- RareTransceiver with an internal short between its bus pins
- Repair
- Hard · Usually a job for a workshop.Typical cost: €80 – €1,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.