Code result
P04D4
Exhaust Brake Input Circuit Range or Performance
Moderate severity
What it means
Same as P04D3 with the signal in plausible range yet not matching expected behaviour - e.g. activation request without driver input or no response after a request.
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
Signal implausible against driver action or bus
highOne of the most commonly reported causes for this code — check this first.
Related help
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