Incorrect fluid level

Add fluid to the proper level. Refer to Transmission Fluid Check.

Sticking valves in control valve body assembly

Rebuild the control valve body assembly. Refer to Control Valve Body Replacement.

Low main pressure

Refer to Low Main Line Pressure in All Ranges and Low Main Line Pressure in Specific Ranges, Normal Pressure in Other Ranges.

Leaking pressure control solenoids

Repair or replace the pressure control solenoids. Refer to Control Valve Solenoid Replacement.

Erratic speed sensor signal

Refer to the speed sensor DTCs.

Piston seals leaking or clutch plates slipping in range involved

Overhaul the transmission.