Code result
U3551
Hydrogen Tank A Valve Enable Circuit
High severity
What it means
Hydrogen Tank A Valve Enable Circuit: an electrical fault is present in the circuit.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Enable wire open or relay failed
highOne of the most commonly reported causes for this code — check this first.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
CAN terminating resistor (120 Ω) drifted out of spec
lowLess common, but worth ruling out after the more likely causes.
Related help
Get the full diagnosis
Add your vehicle and see step-by-step repair help, recalls, and TSBs in Wrenchify.
Diagnose U3551 freeNo credit card required