P3412Cylinder 2 Deactivation/Intake Valve Control Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- On GM's L84 V8 each cylinder, including cylinder 2, has a valve lifter oil solenoid bolted into the block valley. NHTSA's description of the system notes these solenoids are driven with peak-and-hold current for fast response. P3412 is set when the control line for cylinder 2 is shorted to supply voltage: GM checks it with the driver on and treats under 0.5 ohm to power as failed, 20 of 25 samples at 250 ms, Type B. In that state the computer cannot pull the solenoid properly and drops cylinder 2 from deactivation. Related codes are P3409 for an open circuit, P3411 for a short to ground and P3410 when the circuit is fine but the cylinder does not respond.
- What you may notice
- Check engine lamp on
- Cylinder deactivation no longer active
- Likely causes
- LikelyControl wire shorted to a voltage feed in the harness
- PossibleLow-resistance coil in the cylinder 2 solenoid
- RareEngine control module output stage fault
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €60 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.