B0237
Backup Lamp Circuit
The body control module has detected a fault in the backup (reverse) lamp circuit. The lamp does not match the commanded state when reverse gear is engaged.
- 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.
- Bulb burned outCommon
- Reverse switch failedPossible
Parts involved
- Backup Lamp
- Reverse Switch
- Body Wiring Harness
B0237 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.