P25D0 code meaning
Exhaust Camshaft Actuator Park Lock Control Circuit/Open (Bank 1)
Powertrain system Generic code P25xx codes Check engine light
What P25D0 means
P25D0 moves the open-circuit lock fault to the exhaust side: the solenoid that releases the locking pin of the bank 1 exhaust cam phaser can no longer be driven because its circuit is interrupted or reads implausibly. The lock keeps the exhaust cam at a defined position while the engine starts, before the phaser has enough oil pressure to hold itself. No manufacturer documents P25D0 publicly; GM's 2015 Volt table names only the intake lock codes, and BorgWarner's mid-position lock for the Hyundai Gamma II four-cylinder is fitted on the intake cam while the exhaust phaser has none. The background therefore rests on CARB's rules for variable valve timing and output circuits. Without lock control the exhaust timing stays fixed, which costs economy and raises emissions.
P25D0 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P25D0
- Check engine lamp on
- Slightly higher fuel consumption
- Rough idle possible
Common causes of P25D0
- Most likelyOpen winding in the exhaust phaser lock solenoid
- PossibleConnector damaged by exhaust heat
- PossibleBroken wire to the exhaust lock solenoid
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Exhaust cam phaser b1Park lock solenoidWiring harness
What each part of P25D0 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. |
| D0 | The exact fault in that area. |
What to do next
- Note P25D0 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 P25D0
What does P25D0 mean?
P25D0 means "Exhaust Camshaft Actuator Park Lock Control Circuit/Open (Bank 1)". P25D0 moves the open-circuit lock fault to the exhaust side: the solenoid that releases the locking pin of the bank 1 exhaust cam phaser can no longer be driven because its circuit is interrupted or reads implausibly. It is a generic code, so it means the same on every make.
Is it safe to drive with P25D0?
Drive gently and only to a workshop. With P25D0 the car can go into limp mode (reduced power) to protect itself.
Will P25D0 fail an emissions test?
Yes, it can. P25D0 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 P25D0 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will P25D0 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.