Code result
P259C
Excessive Time To Enter Closed Loop Turbocharger A Boost Control
Moderate severity
What it means
After start-up the boost-control loop on turbo A takes longer than the calibration limit to transition from open-loop to closed-loop control. Typically a slow-warming actuator (VGT vanes carbonised), a sluggish position sensor or a leaky pneumatic actuator that cannot follow setpoints quickly enough.
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
Carbonised VGT vanes
highOne of the most commonly reported causes for this code — check this first.
Leaky pneumatic actuator
mediumA plausible cause — test and verify before replacing parts.
Related help
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