Code result
P3408
Cylinder 1 Deactivation Circuit Low Voltage
Moderate severity
What it means
The engine control module has detected low voltage on the cylinder 1 deactivation control circuit. Variant of P3404 reported on platforms with separate diagnostic ranges.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Wiring shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Solenoid internally shorted
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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