B0156
Sun Load Sensor Circuit
The HVAC control module has detected an implausible signal from the sun load (solar) sensor, typically located on the dashboard. Automatic climate control uses this signal to bias cooling on the side facing the sun.
- 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.
- Sun load sensor failedCommon
- Wiring or connector faultPossible
Parts involved
- Sun Load Sensor
- Hvac Control Module
B0156 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.