Cylinder 1 Deactivation/Intake Valve Control Circuit Open
What does P3401 mean?
The P3401 code means the vehicle's onboard diagnostic system has detected: Cylinder 1 Deactivation/Intake Valve Control Circuit Open. This is a moderate severity code.
Common Symptoms
- Check Engine Light on
- Rough idle when deactivation engages
- Engine vibration
- Ticking noise from cylinder 1 area
- Reduced fuel economy
Probable Causes (Ranked by Likelihood)
- Failed cylinder 1 deactivation solenoid Very High
- Open circuit in the solenoid wiring High
- Corroded connector at the deactivation solenoid Moderate
- ECM driver circuit fault for cylinder 1 Moderate
- Low oil pressure to the solenoid Low
Step-by-Step Diagnostic Procedure
-
Test the cylinder 1 deactivation solenoid resistance -- compare to spec
-
Inspect the solenoid wiring and connector for open circuits or corrosion
-
Verify power and ground at the solenoid connector
-
Check engine oil level and pressure
-
Replace the solenoid if resistance is out of spec
Frequently Asked Questions
What does open circuit mean for the deactivation solenoid?
An open circuit means electrical current cannot flow through the solenoid, either because the solenoid coil has failed internally or because a wire is broken between the ECM and the solenoid.
Are deactivation solenoids hard to replace?
Difficulty varies by vehicle. On some GM trucks, the solenoids are accessible under the valve cover. On other vehicles, significant disassembly may be required.
Can I drive with one deactivation solenoid not working?
Yes, the engine will run normally but the cylinder deactivation system will be disabled or operate incorrectly. You may see reduced fuel economy.