Code result
P049F
Exhaust Pressure Control Valve B
Moderate severity
What it means
A general circuit fault is detected on the second exhaust pressure control valve (B) - used for example on dual exhaust brakes, twin-bank diesels with separate back-pressure flaps, or for DPF regeneration backpressure assist on the second bank. The ECU loses control of this stage.
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
Open in harness or actuator winding
highOne of the most commonly reported causes for this code — check this first.
Connector corroded by exhaust heat or moisture
mediumA plausible cause — test and verify before replacing parts.
Related help
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