Code result
B0240
Headlamp Switch Circuit
Moderate severity
What it means
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?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Headlamp switch worn or failed
highOne of the most commonly reported causes for this code — check this first.
Wiring or connector fault
mediumA plausible cause — test and verify before replacing parts.
Related help
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