Powertrain, shared range

P3472 Cylinder 9 Exhaust Valve Control Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P3472 records a high voltage level on the cylinder 9 exhaust valve control circuit, the pattern of a wire shorted to a supply feed or of a coil with shorted windings. No manufacturer documents this code publicly; J2012 reserves the codes for cylinders 9 to 12 for engines with more than eight cylinders. Engines that could in principle have a cylinder 9 with deactivation include the Mercedes M137 V12, the Lamborghini Aventador V12 and Bentley's W12; for none of them is a separate exhaust actuator documented, and the Bentley engine is described as leaving its valves working during shut-off. A US patent from GM shows that the exhaust side has a sequence of its own: there the exhaust valves stop before the intake valves and also return first. P3469 (open) and P3471 (low) complete the electrical set.

Likely causes

Exhaust actuator wire of cylinder 9 shorted to voltage
Shorted windings in the exhaust actuator
Faulty engine control module output

Symptoms

  • Check engine lamp on
  • Cylinder deactivation switched off by the control module

Repair estimate

DifficultyMediumDIY possible
Parts and labour€60–900
Time0.5–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

cylinder deactivation solenoidwiring harnessecm

Related codes

P3469P3470P3471P3468P3497

References: law.cornell.edu, patents.google.com, mobilityengineeringtech.com, en.wikipedia.org.