P25D4 code meaning
Exhaust Camshaft Actuator Park Lock Control Circuit Low (Bank 2)
Powertrain system Generic code P25xx codes Check engine light
What P25D4 means
P25D4 reports a lock control line for the bank 2 exhaust phaser that is pulled down below its expected level. Grounding through damaged insulation, a solenoid with shorted turns or oil that has crept into the connector are the usual explanations. Because the exhaust manifold of the second bank radiates onto nearby harness sections, heat sleeving that has slipped out of place is worth checking. While the fault is active the controller cannot set the lock reliably and normally freezes exhaust timing on that bank. As with the other exhaust lock codes, there is no public manufacturer documentation; the account rests on CARB's circuit monitoring requirement and the operating principle of locking phasers. Repair is wiring work or a new solenoid.
P25D4 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 3.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P25D4
- Check engine lamp on
- Bank 2 exhaust timing fixed
Common causes of P25D4
- Most likelyHeat sleeve slipped, wire grounded at the manifold
- PossibleShorted turns in the bank 2 exhaust lock solenoid
- Less likelyOil in the connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Exhaust cam phaser b2Park lock solenoidWiring harness
What each part of P25D4 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. |
| D4 | The exact fault in that area. |
What to do next
- Note P25D4 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 P25D4
What does P25D4 mean?
P25D4 means "Exhaust Camshaft Actuator Park Lock Control Circuit Low (Bank 2)". P25D4 reports a lock control line for the bank 2 exhaust phaser that is pulled down below its expected level. It is a generic code, so it means the same on every make.
Is it safe to drive with P25D4?
Drive gently and only to a workshop. With P25D4 the car can go into limp mode (reduced power) to protect itself.
Will P25D4 fail an emissions test?
Yes, it can. P25D4 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 P25D4 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3.5 hours of work. This is a job for a workshop.
Will P25D4 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.