OBD2 · Powertrain
P34xx codes: cylinder deactivation and valve control
98 codes in this range, all generic — the same meaning on every make. Engines that shut off cylinders at light load to save fuel — and some variable-valve-lift systems — use oil-pressure-controlled lifters or valve actuators on each cylinder. These codes cover their control circuits and performance.
What usually causes codes in this area
- Low, old or wrong-grade engine oil
- Failed deactivation solenoids
- Collapsed or sticking lifters
- Wiring to the valve-control solenoids
Can you keep driving?
Usually drivable — the engine keeps every cylinder running — but check the oil level first, and don’t ignore a ticking noise: a stuck lifter can damage the camshaft.
All P34xx codes
| Code | Meaning |
|---|---|
| P3400 | Cylinder Deactivation System (Bank 1) |
| P3401 | Cylinder 1 Deactivation/Intake Valve Control Circuit/Open |
| P3402 | Cylinder 1 Deactivation/Intake Valve Control Performance |
| P3403 | Cylinder 1 Deactivation/Intake Valve Control Circuit Low |
| P3404 | Cylinder 1 Deactivation/Intake Valve Control Circuit High |
| P3405 | Cylinder 1 Exhaust Valve Control Circuit/Open |
| P3406 | Cylinder 1 Exhaust Valve Control Performance |
| P3407 | Cylinder 1 Exhaust Valve Control Circuit Low |
| P3408 | Cylinder 1 Exhaust Valve Control Circuit High |
| P3409 | Cylinder 2 Deactivation/Intake Valve Control Circuit/Open |
| P3410 | Cylinder 2 Deactivation/Intake Valve Control Performance |
| P3411 | Cylinder 2 Deactivation/Intake Valve Control Circuit Low |
| P3412 | Cylinder 2 Deactivation/Intake Valve Control Circuit High |
| P3413 | Cylinder 2 Exhaust Valve Control Circuit/Open |
| P3414 | Cylinder 2 Exhaust Valve Control Performance |
| P3415 | Cylinder 2 Exhaust Valve Control Circuit Low |
| P3416 | Cylinder 2 Exhaust Valve Control Circuit High |
| P3417 | Cylinder 3 Deactivation/Intake Valve Control Circuit/Open |
| P3418 | Cylinder 3 Deactivation/Intake Valve Control Performance |
| P3419 | Cylinder 3 Deactivation/Intake Valve Control Circuit Low |
| P3420 | Cylinder 3 Deactivation/Intake Valve Control Circuit High |
| P3421 | Cylinder 3 Exhaust Valve Control Circuit/Open |
| P3422 | Cylinder 3 Exhaust Valve Control Performance |
| P3423 | Cylinder 3 Exhaust Valve Control Circuit Low |
| P3424 | Cylinder 3 Exhaust Valve Control Circuit High |
| P3425 | Cylinder 4 Deactivation/Intake Valve Control Circuit/Open |
| P3426 | Cylinder 4 Deactivation/Intake Valve Control Performance |
| P3427 | Cylinder 4 Deactivation/Intake Valve Control Circuit Low |
| P3428 | Cylinder 4 Deactivation/Intake Valve Control Circuit High |
| P3429 | Cylinder 4 Exhaust Valve Control Circuit/Open |
| P3430 | Cylinder 4 Exhaust Valve Control Performance |
| P3431 | Cylinder 4 Exhaust Valve Control Circuit Low |
| P3432 | Cylinder 4 Exhaust Valve Control Circuit High |
| P3433 | Cylinder 5 Deactivation/Intake Valve Control Circuit/Open |
| P3434 | Cylinder 5 Deactivation/Intake Valve Control Performance |
| P3435 | Cylinder 5 Deactivation/Intake Valve Control Circuit Low |
| P3436 | Cylinder 5 Deactivation/Intake Valve Control Circuit High |
| P3437 | Cylinder 5 Exhaust Valve Control Circuit/Open |
| P3438 | Cylinder 5 Exhaust Valve Control Performance |
| P3439 | Cylinder 5 Exhaust Valve Control Circuit Low |
| P3440 | Cylinder 5 Exhaust Valve Control Circuit High |
| P3441 | Cylinder 6 Deactivation/Intake Valve Control Circuit/Open |
| P3442 | Cylinder 6 Deactivation/Intake Valve Control Performance |
| P3443 | Cylinder 6 Deactivation/Intake Valve Control Circuit Low |
| P3444 | Cylinder 6 Deactivation/Intake Valve Control Circuit High |
| P3445 | Cylinder 6 Exhaust Valve Control Circuit/Open |
| P3446 | Cylinder 6 Exhaust Valve Control Performance |
| P3447 | Cylinder 6 Exhaust Valve Control Circuit Low |
| P3448 | Cylinder 6 Exhaust Valve Control Circuit High |
| P3449 | Cylinder 7 Deactivation/Intake Valve Control Circuit/Open |
| P3450 | Cylinder 7 Deactivation/Intake Valve Control Performance |
| P3451 | Cylinder 7 Deactivation/Intake Valve Control Circuit Low |
| P3452 | Cylinder 7 Deactivation/Intake Valve Control Circuit High |
| P3453 | Cylinder 7 Exhaust Valve Control Circuit/Open |
| P3454 | Cylinder 7 Exhaust Valve Control Performance |
| P3455 | Cylinder 7 Exhaust Valve Control Circuit Low |
| P3456 | Cylinder 7 Exhaust Valve Control Circuit High |
| P3457 | Cylinder 8 Deactivation/Intake Valve Control Circuit/Open |
| P3458 | Cylinder 8 Deactivation/Intake Valve Control Performance |
| P3459 | Cylinder 8 Deactivation/Intake Valve Control Circuit Low |
| P3460 | Cylinder 8 Deactivation/Intake Valve Control Circuit High |
| P3461 | Cylinder 8 Exhaust Valve Control Circuit/Open |
| P3462 | Cylinder 8 Exhaust Valve Control Performance |
| P3463 | Cylinder 8 Exhaust Valve Control Circuit Low |
| P3464 | Cylinder 8 Exhaust Valve Control Circuit High |
| P3465 | Cylinder 9 Deactivation/Intake Valve Control Circuit/Open |
| P3466 | Cylinder 9 Deactivation/Intake Valve Control Performance |
| P3467 | Cylinder 9 Deactivation/Intake Valve Control Circuit Low |
| P3468 | Cylinder 9 Deactivation/Intake Valve Control Circuit High |
| P3469 | Cylinder 9 Exhaust Valve Control Circuit/Open |
| P3470 | Cylinder 9 Exhaust Valve Control Performance |
| P3471 | Cylinder 9 Exhaust Valve Control Circuit Low |
| P3472 | Cylinder 9 Exhaust Valve Control Circuit High |
| P3473 | Cylinder 10 Deactivation/Intake Valve Control Circuit/Open |
| P3474 | Cylinder 10 Deactivation/Intake Valve Control Performance |
| P3475 | Cylinder 10 Deactivation/Intake Valve Control Circuit Low |
| P3476 | Cylinder 10 Deactivation/Intake Valve Control Circuit High |
| P3477 | Cylinder 10 Exhaust Valve Control Circuit/Open |
| P3478 | Cylinder 10 Exhaust Valve Control Performance |
| P3479 | Cylinder 10 Exhaust Valve Control Circuit Low |
| P3480 | Cylinder 10 Exhaust Valve Control Circuit High |
| P3481 | Cylinder 11 Deactivation/Intake Valve Control Circuit/Open |
| P3482 | Cylinder 11 Deactivation/Intake Valve Control Performance |
| P3483 | Cylinder 11 Deactivation/Intake Valve Control Circuit Low |
| P3484 | Cylinder 11 Deactivation/Intake Valve Control Circuit High |
| P3485 | Cylinder 11 Exhaust Valve Control Circuit/Open |
| P3486 | Cylinder 11 Exhaust Valve Control Performance |
| P3487 | Cylinder 11 Exhaust Valve Control Circuit Low |
| P3488 | Cylinder 11 Exhaust Valve Control Circuit High |
| P3489 | Cylinder 12 Deactivation/Intake Valve Control Circuit/Open |
| P3490 | Cylinder 12 Deactivation/Intake Valve Control Performance |
| P3491 | Cylinder 12 Deactivation/Intake Valve Control Circuit Low |
| P3492 | Cylinder 12 Deactivation/Intake Valve Control Circuit High |
| P3493 | Cylinder 12 Exhaust Valve Control Circuit/Open |
| P3494 | Cylinder 12 Exhaust Valve Control Performance |
| P3495 | Cylinder 12 Exhaust Valve Control Circuit Low |
| P3496 | Cylinder 12 Exhaust Valve Control Circuit High |
| P3497 | Cylinder Deactivation System (Bank 2) |
Read the codes from your own car
Plug an inexpensive Bluetooth LE or Wi-Fi OBD2 adapter into the port under the dashboard, and Brimly on your iPhone reads the stored, pending and permanent codes, explains each one offline and clears them once the fault is fixed. OBD diagnostics are part of Brimly Forever, a one-time purchase.
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