U355BCharge Air Cooler Outlet Pressure Sensor 2 Circuit
- Generic OBD-II code · Network
- Turns on the check-engine light
- Can trigger limp mode
- How the car detects it
- U355B points to a circuit problem with pressure sensor 2 at the charge air cooler outlet. J2012 lists two at this spot, which points to a pair used for cross-checking; how a maker splits the roles is unpublished, and no public document uses U355B. A GM patent shows the principle: before start-up, while the compressor stands still and the cathode holds only atmospheric pressure, readings are compared, and a doubtful sensor is replaced by a value calculated from the remaining ones. Ford names a winter risk on the wet air side: water on a sensor diaphragm can freeze and give no or false output at a cold start, which may lead to a shutdown. Sensor 1 at the same spot is U355A. With only one valid sensor left, output may be limited.
- What you may notice
- Fuel cell system warning, MIL on
- Start refused or system shuts down shortly after a cold start
- Reduced power while only one pressure sensor is valid
- Likely causes
- LikelyOpen, short or corrosion in wiring or connector of sensor 2
- PossibleCondensed water frozen on the sensor (occurs at cold start, may clear when warm)
- PossiblePressure sensor 2 faulty internally
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.