OBD-II code · Powertrain (generic, extended)

P25E9 Supercharger Disconnect Clutch Stuck Open

The clutch that engages the mechanical supercharger to the engine drive will not close. The supercharger stays disengaged so boost from this stage is unavailable, which limits torque and may also affect cooling pump drives shared with the same belt.

Is it safe to drive with P25E9?

Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.

Common causes

  • Most likelyOpen electromagnetic clutch coil
  • PossibleWorn friction surfaces leave the air gap too large to attract
  • Less likelyCorroded armature plate stuck open

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
2–6 h
Emissions test
Usually unaffected
Parts involved
Supercharger Clutch, Clutch Solenoid, Clutch Pulley

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.