Code result
P28D9
Clutch B Motor Underspeed
High severity
What it means
The clutch B actuator motor falls below the calibrated minimum speed for the commanded duty. High mechanical load or supply voltage low.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Mechanical load increased (binding)
highOne of the most commonly reported causes for this code — check this first.
Supply voltage low under load
mediumA plausible cause — test and verify before replacing parts.
Related help
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