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DTC codes / P34xx · Auxiliary emission controls / P3444

P3444Cylinder 6 Deactivation/lntake Valve Control Circuit High

P3444 indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the control circuit for the cylinder 6 deactivation/intake valve, which is part of a variable displacement or cylinder deactivation system. The PCM expects a certain voltage range when commanding the valve, and a high reading suggests an open circuit, short to power, or a faulty valve solenoid.

SystemPowertrain
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyIntermediate
AreaAuxiliary emission controls

Symptoms you may notice

  • Illumination of the check engine light, often with no other noticeable symptoms.
  • Rough engine idle or vibration due to cylinder 6 remaining active or inactive when it should not be.
  • Reduced fuel economy because the engine cannot enter cylinder deactivation mode efficiently.
  • Possible misfire or hesitation under light load if the valve fails to actuate properly.
  • In some cases, the engine may enter limp mode or limit power to protect the valvetrain.

Common causes, most likely first

  1. Open or damaged wire in the cylinder 6 deactivation valve control circuit.
  2. Short to voltage on the control circuit, often due to chafed insulation or moisture intrusion.
  3. Failed cylinder 6 deactivation/intake valve solenoid or actuator.
  4. Corroded or loose electrical connector at the valve or PCM.
  5. Internal PCM driver fault, though this is less common.
  6. Mechanical binding of the valve or lifter preventing proper movement, which can affect circuit feedback.

How to diagnose and fix it

  1. Scan all modules for stored codes and freeze-frame data to confirm P3444 is active and not history.
  2. Visually inspect the cylinder 6 deactivation valve connector and wiring for damage, corrosion, or loose pins.
  3. Measure resistance of the valve solenoid with a multimeter and compare to manufacturer specifications.
  4. Check for voltage on the control circuit with the key on and engine off, looking for an unexpected high voltage.
  5. Perform a wiggle test on the harness while monitoring live data to catch intermittent opens or shorts.
  6. If the circuit and solenoid test good, suspect the PCM and perform pinpoint tests according to the service manual.
  7. Repair or replace the faulty wiring, connector, solenoid, or PCM as needed, then clear codes and verify the repair.

Don't overlook the harness before replacing the valve

  • A high voltage code often results from a simple open circuit, such as a broken wire near the valve cover, rather than a failed solenoid.
  • Moisture or oil intrusion into the connector can create a high-resistance path that mimics a faulty valve, so always check connector condition first.
  • Some vehicles set this code when the engine oil level is low or degraded, as the deactivation system relies on oil pressure to actuate the valve.
  • The code may be stored alongside misfire codes for cylinder 6, but the misfire could be a symptom of the deactivation fault, not a separate ignition issue.
  • After repairs, a relearn or adaptation reset may be required for the cylinder deactivation system to function correctly.

Can I keep driving with P3444?

You can usually drive the vehicle with P3444 set, but avoid heavy loads and prolonged high-speed driving until the fault is repaired. If the engine runs rough or enters limp mode, seek service promptly to prevent potential damage to the valvetrain or catalytic converter.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

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