P28CA
Clutch A Motor Underspeed
What it means
P28CA means Clutch A Motor Underspeed.
Check these first
- A clutch A motor turning slower than commanded
- Low supply voltage to the clutch A motor
- Mechanical drag in the clutch A actuator
- Contaminated fluid increasing clutch A motor load
- A worn clutch A motor winding
What to do next
- Read clutch A motor speed on a scan tool
- Command the clutch A motor and compare actual to commanded speed
- Check battery voltage and the clutch A motor power feed
- Inspect the clutch A actuator for mechanical drag
- Replace the clutch A motor if speed stays low
- Clear the code and retest
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Updated
Generic SAE J2012 definition. Last updated 2026-10-10.