P3472: Cylinder 9 Exhaust Valve Control Circuit High

What does P3472 mean?

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.

The code tells you which monitor failed, not which part is broken. Test before replacing parts.

Symptoms

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

Common causes

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

Likelihood is a general estimate across vehicles; your make and model may differ.