The clutch for lock-up has jammed in the closed position.
â–¶ How to fix
Contact an Allison dealer.
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
Detection
The control unit has detected that the torque converter lock-up clutch is slipping.
Possible cause
Possible fault on the solenoid which controls the lock-up.