Code result
B0173
HVAC Air Inlet Door
Moderate severity
What it means
The HVAC control module has detected a fault on the fresh-air/recirculation inlet door — typically a stuck actuator or position feedback out of range.
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
Inlet door actuator failed
highOne of the most commonly reported causes for this code — check this first.
Inlet door mechanically binding
mediumA plausible cause — test and verify before replacing parts.
Related help
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