What it means
The exhaust camshaft actuator park-lock circuit on bank 2 is below the expected electrical threshold. This indicates a low circuit condition, not necessarily a specific short or internal driver failure.
At a glance
- Usually lights the check-engine light
How it works
The exhaust camshaft actuator park-lock solenoid on bank 2 uses an electrical control circuit to help hold the exhaust phaser in its parked position. P25D4 means the module detects the circuit voltage below its expected range; it does not identify whether a grounded wire, poor connection, or driver fault caused it.
Common causes
Most likely first.
- Control wire shorted to ground
- ECU low-side driver internally shorted
- Connector pins corroded - high contact resistance
Symptoms
- Check engine light on
- Power loss especially in mid-rpm range
- Possible rough idle or stalling
- Increased fuel consumption
How to diagnose it
- Record freeze-frame data and check for related exhaust camshaft actuator codes before clearing anything.
- Inspect the bank 2 park-lock solenoid connector and harness for corrosion, pin damage, or a wire pinched against ground.
- Check the connector terminals for corrosion or weak contact that could lower the circuit signal.
- Following the manufacturer's procedure, measure the circuit condition at the solenoid connector and test the control wire for a short to ground.
- If the wiring and connections test correctly, check the control module's low-side output using the manufacturer's procedure.
Common fixes
- Clean or repair corroded terminals at the bank 2 solenoid connector.
- Repair a control wire shorted to ground.
- Replace the park-lock solenoid if testing confirms an internal fault.
- Repair the control module output only if circuit tests confirm its driver is faulty.
Can I keep driving?
If the engine runs normally and the check-engine light is steady, drive gently and avoid hard acceleration until the circuit is checked. Stop if it stalls, becomes very rough, or loses substantial power.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.