P25AE code meaning
Piston Cooling Oil Pressure Too Low
Powertrain system Generic code P25xx codes Check engine light
What P25AE means
P25AE means the oil pressure reaching the piston cooling jets is below what the engine controller requires, even though the valve circuit itself shows no electrical fault. Volvo and Mack heavy trucks store it as P25AE00. Their bulletins KC-170 (2020, reissued 2021) and CBR 170-8 (May 2025, Mack and Volvo chassis from 2007 onward) cover an inactive P25AE00 set after a hard pull when engine oil pressure briefly drops, with SPN 4811 and SPN 100 named as related. Before parts are swapped, the oil temperature reading is compared with an infrared thermometer; a gap above 5 °F means a new sensor, otherwise technical support takes over. Real causes include low oil level, a tired pump or blocked jets. Lasting low cooling pressure endangers the pistons, so engines may derate.
P25AE at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 8 hours
- Clears after repairAfter a drive cycle
Symptoms of P25AE
- Inactive code after heavy pulling
- Low oil pressure warning at the same time
- Engine derate possible
Common causes of P25AE
- Most likelyLow oil level or oil starvation under hard load
- PossibleOil temperature sensor reading wrong (Volvo/Mack bulletin)
- PossibleWorn oil pump or leaking pressure relief valve
- Less likelyClogged oil filter or piston cooling jets
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Oil pumpOil galleryPiston cooling solenoid
What each part of P25AE means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| AE | The exact fault in that area. |
What to do next
- Note P25AE and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P25AE
What does P25AE mean?
P25AE means "Piston Cooling Oil Pressure Too Low". P25AE means the oil pressure reaching the piston cooling jets is below what the engine controller requires, even though the valve circuit itself shows no electrical fault. It is a generic code, so it means the same on every make.
Is it safe to drive with P25AE?
Drive gently and only to a workshop. With P25AE the car can go into limp mode (reduced power) to protect itself.
Will P25AE fail an emissions test?
Yes, it can. P25AE is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P25AE to fix?
Difficulty: hard. A typical repair takes 0.5 to 8 hours of work. This is a job for a workshop.
Will P25AE clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.