Code result
B0040
Outside Temperature Sensor Circuit
Moderate severity
What it means
The HVAC or body control module has detected an implausible signal from the outside (ambient) temperature sensor. The displayed outside temperature may be wrong or missing and automatic climate control may behave incorrectly.
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
Ambient temperature sensor failed
highOne of the most commonly reported causes for this code — check this first.
Wiring or connector fault to sensor
mediumA plausible cause — test and verify before replacing parts.
Related help
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