P25AC

What it means

The control circuit is electrically intact, but the solenoid valve does not open when commanded — confirmed by oil-pressure or oil-temperature feedback that does not change after the activation pulse. Piston cooling does not engage under high load — risk of piston-crown overheating and ring-land cracks.

Is it safe to drive?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

• Solenoid stuck closed by oil sludge

  high

  One of the most commonly reported causes for this code — check this first.

• Carbon or debris buildup preventing free movement

  low

  Less common, but worth ruling out after the more likely causes.

• Component wear with age - mechanical play

  low

  Less common, but worth ruling out after the more likely causes.

Related help

• Full P25AC diagnosis, causes & costs
• How to read check engine light codes
• Is it safe to drive with the light on?