B0158
Ambient Air Temperature Sensor Circuit
The HVAC control module has detected an implausible signal from the ambient air temperature sensor used by the climate control system. Symptoms include incorrect outside temperature display and erratic automatic climate behavior.
- Check engine light: Not always
- Emissions related: No
- Repair difficulty: easy
Symptoms
- Warning light or symbol related to the affected system
- Comfort or safety function impaired
Common causes
Ordered by how often each turns out to be the cause.
- Ambient air temperature sensor failedCommon
- Wiring or connector faultPossible
Parts involved
- Ambient Air Temperature Sensor
- Hvac Control Module
B0158 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.