P3496Cylinder 12 Exhaust Valve Control Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P3496 is the final code of the per-cylinder valve block: it marks the cylinder 12 exhaust valve control circuit as too high, typically a short to battery voltage or a coil with shorted turns. No manufacturer documents this code publicly; J2012 reserves the codes for cylinders 9 to 12 for engines with more than eight cylinders. Bentley built its last W12 in 2024 after describing a shut-off that idles one bank of six under part or trailing throttle, and the Lamborghini Aventador V12 shut one bank below 135 km/h; neither documents an exhaust actuator for cylinder 12. The clearest public account of exhaust valves following their own switching sequence remains a GM patent. Should the code appear, the module will disable deactivation. P3493 (open) and P3495 (low) complete the set, P3497 is the bank 2 system code.
- What you may notice
- Check engine lamp on
- Cylinder shut-off disabled
- Likely causes
- PossibleExhaust actuator wire of cylinder 12 shorted to battery voltage
- PossibleShorted turns in the exhaust actuator coil
- 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.