OBD-II code · Powertrain (generic, extended)
P28F4 Engine Disconnect Clutch Pressure Sensor Circuit High
Voltage on the engine disconnect clutch pressure sensor signal line is above the expected window. Wire shorted to B+ or sensor open.
Is it safe to drive with P28F4?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelySignal wire shorted to B+
- PossibleOpen pressure sensor
- Less likelyConnector pins corroded - high contact resistance
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 2–9 h
- Emissions test
- Usually unaffected
- Parts involved
- Engine Disconnect Clutch Pressure Sensor, Wiring Harness
Related codes
- P28F1Engine Disconnect Clutch Pressure Sensor Circuit
- P28F2Engine Disconnect Clutch Pressure Sensor Circuit Range/Performance
- P28F3Engine Disconnect Clutch Pressure Sensor Circuit Low
- P28F5Engine Disconnect Clutch Pressure Sensor Circuit Intermittent/Erratic
- P28F6Engine Disconnect Clutch Actuator Circuit Intermittent
- P28F7Exhaust Pressure Too High Bank 1
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.