OBD-II code · Powertrain (generic, extended)
P28D2 Clutch B Phase U-V-W Circuit Low
The output stage for the clutch B BLDC motor reports a low phase voltage on at least one of the U/V/W phases. Short to ground or interrupted half-bridge.
Is it safe to drive with P28D2?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyPhase wire shorted to ground
- PossibleLow-side switch open in driver
- 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
- 3–10 h
- Emissions test
- Usually unaffected
- Parts involved
- Clutch Motor B, Wiring Harness, Tcm
Related codes
- P28C4Clutch A Phase U-V-W Circuit Low
- P28CFClutch A Pressure Sensor Circuit High
- P28D0Clutch A Pressure Sensor Circuit Range/Performance
- P28D1Clutch A Motor Driver Current/Temperature Too High
- P28D3Clutch B Phase U-V-W Circuit High
- P28D4Clutch B Phase U-V-W Circuit/Open
- P28D5Clutch B Phase U-V-W Performance
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.