Solenoid PCS3 jammed in connected 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
PCS3 still supplies a clutch despite that the clutch should be shut off. The fault is detected when the control unit detects that a previous gear change remained engaged for a long time period despite the clutch having received a signal to be shut off.
Possible cause
The cause can be: Erratic sensor signal from turbine or output shaft speed.Obstruction in a discharge circuit for clutches C3 or C4.Faulty PCS3 solenoid.A governor valve for PCS3 is stuck.