P28CEClutch A Pressure Sensor Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P28CE is logged when the clutch A pressure sensor output drops below the lowest voltage a working sensor can produce. Ratiometric pressure sensors are usually designed so that even zero pressure gives a small offset voltage; a reading underneath that band therefore means an electrical fault, not low pressure. Classic causes are a signal wire shorted to ground, a collapsed 5-volt reference shared with other sensors, or an internal short in the sensor. If the reference is the problem, several sensor codes often appear together. The pressure closed loop of the pump actuator then lacks feedback and clutch A is typically switched off. P28CF is the high-side twin; no manufacturer publicly documents P28CE values.
- What you may notice
- Clutch A disabled with transmission warning
- Other sensor codes may be stored at the same time
- Reduced choice of gears
- Likely causes
- LikelyPressure sensor signal wire shorted to ground
- Possible5-volt reference pulled down by another sensor on the same supply
- PossibleInternally shorted clutch A pressure sensor
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- 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.