P3489 code meaning
Cylinder 12 Deactivation/Intake Valve Control Circuit/Open
Powertrain system Generic code P34xx codes Check engine light
What P3489 means
P3489 reports that the circuit to the actuator for deactivation or the intake valve of cylinder 12, the highest cylinder number in this code series, is open. No manufacturer documents this code publicly; J2012 reserves the codes for cylinders 9 to 12 for engines with more than eight cylinders. Twelve-cylinder engines with shut-off span Mercedes' late-1990s V12, which deactivated every second cylinder in the firing order, Lamborghini's Aventador V12 that shuts down one cylinder bank below 135 km/h, and Bentley's W12. The Mercedes engine used a hydraulic solenoid pack, the kind of part such a circuit would drive; the bank-based systems publish no equivalent. Comparable logic on GM V8s calls a circuit open above 200 kohm with the output idle. P3491 and P3492 report shorts, P3490 a functional fault, P3493 the exhaust valve.
P3489 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P3489
- Check engine lamp on
- Engine no longer runs in reduced-cylinder mode
- Somewhat higher fuel use on the highway
Common causes of P3489
- Most likelyWire to the cylinder 12 actuator open or chafed
- PossibleCylinder 12 actuator coil open
- PossibleLoose or corroded connector at cylinder 12
- Less likelyOutput stage of the control module failed
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Cylinder deactivation solenoidWiring harnessECM
What each part of P3489 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 3 | Mixed range: generic and manufacturer-specific codes. |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| 89 | The exact fault in that area. |
What to do next
- Note P3489 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P3489
What does P3489 mean?
P3489 means "Cylinder 12 Deactivation/Intake Valve Control Circuit/Open". P3489 reports that the circuit to the actuator for deactivation or the intake valve of cylinder 12, the highest cylinder number in this code series, is open. It is a generic code, so it means the same on every make.
Is it safe to drive with P3489?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P3489 fail an emissions test?
Yes, it can. P3489 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P3489 to fix?
Difficulty: medium. A typical repair takes 0.5 to 4 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P3489 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.