HomeTrouble CodesP3472

P3472 — Cylinder 9 Exhaust Valve Control Circuit High

Manufacturer-specificPowertrain (engine & transmission)

P3472 indicates that the powertrain control module (PCM) has detected a high voltage condition on the control circuit for the cylinder 9 exhaust valve actuator, typically a solenoid or variable‑valve‑timing (VVT) oil‑control valve. In normal operation the PCM commands the actuator to adjust exhaust‑valve timing or lift; a high‑circuit reading means the expected ground or low‑side control is not present, preventing proper valve operation for that cylinder. The code is set when the commanded state does not match the observed circuit voltage.

Symptoms

What causes it — most likely first

1. Faulty exhaust valve control solenoid (OCV/VVT actuator)

The solenoid that drives the cylinder‑9 exhaust valve can internally short or stick, causing the circuit to read high voltage.

2. Wiring or harness damage

An open, short, or high‑resistance condition in the signal wire between the PCM and the actuator can produce a high‑voltage reading.

3. Corroded or loose connector

Moisture, corrosion, or poor pin contact at the actuator connector can prevent proper grounding and create a high‑circuit condition.

4. Low oil pressure or contaminated oil

If engine oil pressure is insufficient or the oil is dirty, the actuator may not move correctly, leading to abnormal circuit voltages.

5. Blocked oil passages to the actuator

Sludge or carbon buildup can restrict oil flow to the variable‑valve‑timing mechanism, affecting actuator operation.

6. PCM software/hardware fault (rare)

A malfunction within the PCM that misinterprets the circuit voltage can set P3472, but this should be confirmed only after all other components have been verified.

How it's diagnosed

  1. Retrieve all stored codes and freeze‑frame data to confirm P3472 and any related cylinder‑specific or VVT codes.
  2. Visually inspect the cylinder‑9 exhaust valve actuator connector and wiring harness for damage, corrosion, or looseness.
  3. Measure the actuator’s resistance with a multimeter and compare to the manufacturer’s specification; also check for shorts to ground or power.
  4. Verify engine oil pressure is within specification and inspect oil level and condition.
  5. Check the control circuit for unexpected voltage using a multimeter or oscilloscope while the PCM commands the actuator on and off.
  6. If the actuator, wiring, and oil system all test normal, suspect a PCM issue and verify with factory‑level programming or a known‑good replacement module.

Code facts & related codes

SystemPowertrain (engine & transmission)
StandardizationManufacturer-specific (P1/B1/C1/U1)

Frequently asked

Will replacing the PCM always fix a P3472?

No. The PCM is rarely the root cause. In most cases the problem is a faulty actuator, wiring issue, or low/ dirty oil. PCM replacement should only be considered after all other components have been verified.

Can low oil cause this code even if the actuator tests good?

Yes. If oil pressure is too low or the oil is contaminated, the actuator may not move correctly, causing an abnormal voltage reading on the circuit.

Is it safe to drive with a P3472?

Driving with a malfunctioning cylinder‑9 exhaust valve can lead to reduced performance, higher emissions, and potential engine damage, so the issue should be addressed promptly.

Why does the code appear only for cylinder 9?

P3472 is specific to the exhaust‑valve control circuit for cylinder 9. Each cylinder with variable valve timing has its own dedicated actuator and circuit; a fault in another cylinder would trigger a different code.