P3468 indicates that the control circuit for the cylinder 9 deactivation or intake valve actuator is pulled high, typically by a short to battery voltage that the module notices once it switches the output on. No manufacturer documents this code publicly; J2012 reserves the codes for cylinders 9 to 12 for engines with more than eight cylinders. Most engines above eight cylinders that shut cylinders down, such as Audi's R8 V10 and Bentley's W12, do so bank by bank without dedicated valve actuators; Mercedes' M137 V12, by contrast, used a solenoid pack. GM's eight-cylinder version of this check counts below 0.5 ohm to controller power with the driver on, 20 of 25 samples. Expect the module to shut the output off and run all cylinders. P3465 (open) and P3467 (ground short) are the other electrical faults here.
Medium severity. Can I keep driving?Drive little and gently. If you hear timing chain noise or the oil light comes on, shut off the engine.
Cylinder 9 is numbered according to the manufacturer: check your engine's manual before working on it.
Symptoms
- Check engine lamp on
- Engine runs on all cylinders at all times
Most likely causes
- Cylinder 9 control wire touching a supply wire
- Shorted turns in the cylinder 9 solenoid coil
- Output stage of the engine control module damaged
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It affects emissions.
What each character of P3468 means
- P: Powertrain: engine and transmission
- 3: Generic or manufacturer code, depending on the range
- 4: Emissions
- 68: Specific fault in that system
Frequently asked questions
Can I keep driving with code P3468?
Drive little and gently. If you hear timing chain noise or the oil light comes on, shut off the engine.
What causes code P3468?
The most common causes are: cylinder 9 control wire touching a supply wire; shorted turns in the cylinder 9 solenoid coil; output stage of the engine control module damaged.
Related codes
- P3465Cylinder 9 Deactivation/Intake Valve Control Circuit/Open
- P3466Cylinder 9 Deactivation/Intake Valve Control Performance
- P3467Cylinder 9 Deactivation/Intake Valve Control Circuit Low
- P3472Cylinder 9 Exhaust Valve Control Circuit High
- P3497Cylinder Deactivation System Bank 2
Sources
- law.cornell.edu: 13 CCR 1968.2
- gsi.ext.gm.com: 19OBDG03B Diagnostics
- media.audiusa.com: 404
- en.wikipedia.org: Mercedes Benz M137 engine
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.