Theory of Operation
WARNING: This page is about a different car, the 2011 RAM Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The Transmission system uses three pressure switches to monitor the fluid pressure in the LR, 2/4, and OD elements. The pressure switches are continuously monitored for the correct states in each gear. The 2/4 pressure switch monitors the fluid pressure to the 2/4 clutch to confirm proper operation of the 2/4 solenoid. If the 2/4 pressure switch is identified as closed in P or N, the code will immediately be set and normal operation will be allowed for that given key start. If the problem is identified for three successive ignition cycles, the transmission will go into Limp-in mode.