P28D9

Clutch B Motor Underspeed

Severity

🔴 High

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$167–556 (est.)

Symptoms

Rough gear shifting
Clutch slipping during acceleration
Jerks when shifting gears
Increased engine speed during acceleration
Transmission transition to emergency mode

Causes

Worn clutch friction discs B
Low or contaminated transmission fluid
Malfunction of the hydraulic control unit
Clutch speed sensor problems
Open or short circuit in clutch control circuit

How to Fix

Check the level and condition of the transmission fluid
Diagnose the condition of clutch B
Check the operation of the hydraulic control unit
Test speed sensors and control circuits
If necessary, replace clutch B or hydraulic unit

Related codes

P28D8 P28DA P28DB