P3492Cylinder 12 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
- P3492 records a high condition on the control circuit of the cylinder 12 deactivation or intake valve actuator, generally a short to a supply voltage seen while the output is commanded on. No manufacturer documents this code publicly; J2012 reserves the codes for cylinders 9 to 12 for engines with more than eight cylinders. The Variable displacement overview notes that a V12 can stop up to six cylinders, and the production engines doing so (Mercedes M137, Lamborghini Aventador, Bentley W12) differ widely in method, from a hydraulic solenoid pack (M137) to bank shut-off with the valves left running (Bentley). Only a design with valve actuators has a cylinder 12 actuator to short. Expect deactivation to be inhibited and the engine to run on all twelve. P3489 and P3491 are the electrical siblings, P3496 the exhaust high code.
- What you may notice
- Check engine lamp on
- Engine runs permanently on twelve cylinders
- Likely causes
- LikelyCylinder 12 control wire shorted to supply voltage
- PossibleShorted turns in the cylinder 12 actuator
- RareEngine control module output damaged
- 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.