Code result
B0300
HVAC Evaporator Temperature Sensor Circuit
Moderate severity
What it means
The HVAC controller reports a fault in the evaporator temperature sensor circuit, used to prevent evaporator icing.
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
Evaporator sensor failure
highOne of the most commonly reported causes for this code — check this first.
Faulty sensor connector
mediumA plausible cause — test and verify before replacing parts.
Related help
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