U0032Vehicle Communication Bus A (+) High
- Generic OBD-II code · Network
- How the car detects it
- U0032 reports excess voltage on the (+) line of Vehicle Communication Bus A, usually from contact with battery voltage. If Bus A is a two-wire CAN of the high-speed type, as Audi's sensor/hybrid CAN, the (+) wire is CAN-High. onsemi's bench tests show frames still getting through with CAN-High at 12 V, only with distorted levels; NXP counts such shorts among hidden bus failures that a plain transceiver does not report. Faults therefore show up as sporadic message errors or a single module complaining while the vehicle behaves normally, quite unlike the hard stop of U0031. No manufacturer documents U0032 publicly. A reading close to battery voltage on CAN-High against ground, instead of somewhere between 2.5 V and 3.5 V, confirms it; a harness rubbed through next to a supply cable or a wet connector is the usual cause.
- What you may notice
- Sporadic warnings or brief function dropouts
- Only one module reports the fault, vehicle otherwise normal
- Likely causes
- Likely(+) wire chafed against a battery or ignition feed
- PossibleWater in a connector bridging the (+) wire to a supply pin
- RareAftermarket device connected to the bus wire
- Repair
- Hard · Usually a job for a workshop.Typical cost: €60 – €700
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.