B0800
Headlamp Switch Circuit
A fault has been detected in the headlamp switch circuit. Light functions may not switch properly.
- Check engine light: Not always
- Emissions related: No
- Repair difficulty: medium
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.
- Headlamp switch internal failureCommon
- Loose switch connectorPossible
Parts involved
- Headlamp Switch
- Body Control Module
B0800 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.