P3460Cylinder 8 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
- P3460 reports a short to supply voltage on the control circuit of the cylinder 8 deactivation solenoid, found while the output is switched on. GM lists it for the 2019 L84: under 0.5 ohm between output and controller power, 20 of 25 samples spaced 250 ms apart, Type B, with the same 11 V and 425 rpm enable limits as the other cylinder 8 circuit checks. GM's table contains a slip here: the strategy column for P3460 speaks of the cylinder 7 solenoid, while code and component name cylinder 8. Typical causes are harness damage against a feed wire or a solenoid with shorted turns; the visible result is that the engine stops using cylinder 8 deactivation. Siblings: P3457 (open) and P3459 (short to ground).
- What you may notice
- Check engine lamp on
- Cylinder deactivation inactive, slightly higher fuel use
- Likely causes
- LikelyCylinder 8 control wire in contact with a voltage source
- PossibleShorted turns in the cylinder 8 solenoid
- RareFaulty driver in the engine control module
- 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.