OBD-II code · Body
B0240 Headlamp Switch Circuit
The body control module has detected an implausible state at the headlamp switch — for example simultaneous low and high beam request, or no signal at all. Lighting functions may be erratic.
Is it safe to drive with B0240?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyHeadlamp switch worn or failed
- PossibleWiring or connector fault
Symptoms
- Warning light or symbol related to the affected system
- Comfort or safety function impaired
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–2 h
- Emissions test
- Usually unaffected
- Parts involved
- Headlamp Switch, Body Control Module
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.