P3408–P3496 Cylinder 1 Exhaust Valve Control Circuit High
The voltage on this circuit is sitting near battery voltage. Typically a short to a positive feed, or a disconnected sensor floating high.
Can you drive it? This class of fault can cause real mechanical damage if you keep driving on it. A persistent misfire also destroys the catalytic converter, which is the expensive part.
Which code is which
Same fault, different cylinder or bank — diagnosed the same way. Several set together usually means one shared cause.
| Code | Definition | Severity |
|---|---|---|
P3408 | Cylinder 1 Exhaust Valve Control Circuit High | Do not keep driving |
P3416 | Cylinder 2 Exhaust Valve Control Circuit High | Do not keep driving |
P3424 | Cylinder 3 Exhaust Valve Control Circuit High | Do not keep driving |
P3432 | Cylinder 4 Exhaust Valve Control Circuit High | Do not keep driving |
P3440 | Cylinder 5 Exhaust Valve Control Circuit High | Do not keep driving |
P3448 | Cylinder 6 Exhaust Valve Control Circuit High | Do not keep driving |
P3456 | Cylinder 7 Exhaust Valve Control Circuit High | Do not keep driving |
P3464 | Cylinder 8 Exhaust Valve Control Circuit High | Do not keep driving |
P3472 | Cylinder 9 Exhaust Valve Control Circuit High | Investigate soon |
P3480 | Cylinder 10 Exhaust Valve Control Circuit High | Do not keep driving |
P3488 | Cylinder 11 Exhaust Valve Control Circuit High | Do not keep driving |
P3496 | Cylinder 12 Exhaust Valve Control Circuit High | Do not keep driving |
The definition
P3408: Cylinder 1 Exhaust Valve Control Circuit High.
P3408 is a manufacturer-specific powertrain code (the engine or gearbox). Its meaning is set by the carmaker rather than by the SAE standard, so a generic OBD-II reader will often show it as an unknown code or misread it.
What to check first
Cheapest and fastest checks first:
- Unplug the sensor and check whether the signal falls. If it stays high, suspect the wiring rather than the sensor.
- Check the earth path - a missing earth makes a sensor read high.
Reading the code is the easy part
A code names the circuit that complained. What tells you why is watching the sensor behind it while the engine runs — and that is where a code reader stops and a diagnostic tool starts.
VAGPULSE reads every module in a VW, Audi, Skoda or SEAT — not just the engine — shows the live measuring blocks behind this fault, gives you the freeze-frame conditions it was logged under, and clears it once you have fixed it. It also does what a generic OBD reader cannot on a VAG: service resets, coding, adaptations, and Stage 1–3 flashing with your original file saved first.
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Common questions
What does P3408 mean?
P3408 means Cylinder 1 Exhaust Valve Control Circuit High. The voltage on this circuit is sitting near battery voltage. Typically a short to a positive feed, or a disconnected sensor floating high.
Can I drive with P3408?
This class of fault can cause real mechanical damage if you keep driving on it. A persistent misfire also destroys the catalytic converter, which is the expensive part.