P3447

Code

Generic P — Powertrain

Cylinder 6 Exhaust Valve Control Circuit Low

Brand: Generic

Type: P — Powertrain

Views: UK: 28 EN: 52 RU: 27

AI status

Completed

ready

Completed 100%

Page language: EN

Check Engine Light (MIL) illuminated
Engine misfire or rough running localized to cylinder 6 under some conditions
Reduced engine power or limp-home mode due to disabled cam control
Poor fuel economy and hesitation during acceleration
Unusual noises from the valve train area (possible with phaser mechanical failure)

Scan for stored and pending DTCs and freeze-frame data (confirm P3447 and related codes)
Check engine oil level and condition; note oil change history
Visually inspect wiring and connector for cylinder 6 exhaust solenoid for damage, corrosion, or loose pins
Backprobe the solenoid connector with ignition on and engine off to confirm reference voltage and ground presence
Attempt to actuate the exhaust valve solenoid with a diagnostic scan tool (if supported) and observe response

Expected control signal: switched battery voltage or PWM from ECM (0–12 V depending on system)
Inactive/low: ~0 V (or near ground) when commanded off; Active/high: near battery voltage (or PWM 0–100% duty) when commanded on
Coil resistance (varies by design): typically tens of ohms (example 5–50 Ω) — consult vehicle-specific spec
PWM frequency: commonly tens to a few hundred Hz (vehicle-specific)

Retrieve and record freeze-frame and readiness data; check for related cam/crank or cylinder misfire codes
Visually inspect harness and connector for cylinder 6 exhaust valve solenoid; repair damaged wiring or connectors before further testing
Check engine oil level and condition; correct low level and change very dirty oil, then clear codes and retest
With connector unplugged, measure solenoid coil resistance and compare to manufacturer specification; an open/very high resistance indicates bad solenoid
With key ON (engine off) backprobe connector and measure voltage while commanding solenoid ON with a scan tool; if no command voltage from ECM, inspect ECM output and wiring for open/short to ground
Perform continuity check between solenoid control pin and ECM pin; check for short to ground or battery
Swap the cylinder 6 exhaust solenoid with another known-good cylinder solenoid (if practical) and see if the code follows the solenoid — confirms solenoid vs wiring/ECM
If wiring and solenoid are good but problem persists, inspect cam phaser mechanically and camshaft position sensors for damage or binding
If all wiring and actuators test good, consider ECM output driver fault and consult manufacturer repair information before ECM replacement

Damaged wire between ECM and cylinder 6 exhaust valve solenoid (open or high resistance)
Corroded/loose connector at the solenoid causing low/erratic voltage
Defective cylinder 6 exhaust VVT/EV solenoid coil (internal open)
Low engine oil pressure or dirty oil preventing solenoid/plunger operation
Mechanical failure of the exhaust cam phaser preventing correct movement