What does it mean?
P3440 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Cylinder 5 Exhaust Valve Control Circuit High . This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms
- MIL (check engine lamp) on and the exhaust valve function locked out
- Weak pull at higher rpm and a generally lifeless engine response
- Slightly rough idle and an uneven exhaust note
- Valve train tick that does not respond to commanded switching
- Fuel consumption higher than usual
- Cylinder 5 misfire codes may accompany this one
Likely causes
- Control wire shorted to a battery-fed circuit within the engine harness
- Open or corroded ground return so the driver output sits high
- Open coil in the exhaust valve control solenoid, leaving the circuit unloaded
- Oil-contaminated, corroded or loose connector terminals
- Exhaust heat damage to the connector or the harness branch
- Failed PCM output driver, considered only after wiring and load checks pass
How to fix it
- Record freeze frame and try to reproduce the fault while commanding the solenoid with a scan tool
- Inspect the connector for oil, corrosion, heat distortion and weak terminal tension
- Back-probe the control wire with the key on and compare it against a healthy solenoid on the same bank
- With solenoid and module unplugged, check the control wire for a short to any power feed
- Measure the coil resistance; an open coil produces this reading with no harness fault at all
- Verify a clean, low-resistance ground return
- Repair the harness or replace the solenoid, then confirm normal switching with output commands and a road test