OBD-II code · Powertrain (manufacturer / generic)
P3404 Cylinder 1 Deactivation Circuit Low Voltage
The engine control module has detected low voltage or a short to ground in the cylinder 1 deactivation control circuit.
Is it safe to drive with P3404?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyWiring shorted to ground
- PossibleSolenoid internally shorted
- Less likelyConnector pins corroded - high contact resistance
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–4 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Cylinder Deactivation Solenoid, Engine Wiring Harness
Related codes
- P3408Cylinder 1 Deactivation Circuit Low Voltage
- P3401Cylinder 1 Deactivation/Intake Valve Control Circuit Open
- P3402Cylinder 1 Deactivation Performance/Stuck Off
- P3403Cylinder 1 Deactivation Stuck On
- P3405Cylinder 1 Deactivation Circuit High Voltage
- P3406Cylinder 1 Deactivation Stuck Off
- P3407Cylinder 1 Deactivation Stuck On
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.