Code result
U355D
Expander Inlet Pressure Sensor 1 Circuit
Moderate severity
What it means
Generic fault on the inlet pressure sensor 1 of the expander (turbine recovering energy from the cathode exhaust on FCEVs).
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
Sensor 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
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