Code result
B0420
Audio System Internal Failure
Moderate severity
What it means
The audio head unit reports an internal self-test failure. Symptoms include silent output, frozen display, or repeated reboots of the infotainment system.
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
Head unit internal fault
highOne of the most commonly reported causes for this code — check this first.
Software update required
mediumA plausible cause — test and verify before replacing parts.
Related help
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