Code result
B0540
Driver Door Ajar Switch Circuit
Moderate severity
What it means
The driver door ajar switch circuit is reporting an implausible signal. The interior light may stay on or door open warning may be incorrect.
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
Corroded door switch / striker
highOne of the most commonly reported causes for this code — check this first.
Wire break in door harness
mediumA plausible cause — test and verify before replacing parts.
Related help
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