Code result
U3573
Coolant Mixing Valve Control Circuit
Moderate severity
What it means
Generic electrical fault on the coolant mixing valve control. The valve blends hot and cold coolant streams to maintain stack temperature.
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
Valve actuator 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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