P25D2 is set when the bank 1 exhaust phaser lock control line carries more voltage than the controller allows in the current switching state, for example because it is shorted to an ignition-fed wire or the solenoid's return is tied to supply. Most output stages detect overcurrent here and switch off, so the lock solenoid loses its command and the pin goes to the position its spring defines. The engine then runs with a fixed exhaust cam until the fault clears. No manufacturer publishes material for P25D2; the explanation uses the J2012 title, CARB's demand for electrical monitoring of output components in variable valve timing systems, and the working principle of locking phasers. Unlike the Low code, a short to power can also damage the driver.
Medium severity. Can I keep driving?Drive little and gently. If you hear timing chain noise or the oil light comes on, shut off the engine.
Bank 1 is the side of the engine with cylinder 1. Inline engines only have this bank.
Symptoms
- Check engine lamp on
- Weaker mid-range pull
Most likely causes
- Lock control wire shorted to an ignition-fed circuit
- Solenoid return path shorted to supply
- Damaged output stage in the engine control module
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It can trigger limp mode.
- It affects emissions.
What each character of P25D2 means
- P: Powertrain: engine and transmission
- 2: Generic code: same on every make
- 5: Speed and idle
- D2: Specific fault in that system
Frequently asked questions
Can I keep driving with code P25D2?
Drive little and gently. If you hear timing chain noise or the oil light comes on, shut off the engine.
What causes code P25D2?
The most common causes are: lock control wire shorted to an ignition-fed circuit; solenoid return path shorted to supply; damaged output stage in the engine control module.
Related codes
- P25D0Exhaust Camshaft Actuator Park Lock Control Circuit/Open (Bank 1)
- P25D1Exhaust Camshaft Actuator Park Lock Control Circuit Low (Bank 1)
- P25D5Exhaust Camshaft Actuator Park Lock Control Circuit High (Bank 2)
- P25CCIntake Camshaft Actuator Park Lock Control Circuit High (Bank 1)
- P2091"B" Camshaft Position Actuator Control Circuit High (Bank 1)
Sources
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.