scan the PCM, it will tell you what error you have, called DTC's what other cars did is of on importance, what matters is your car. lets say the connector is just dirty. the side of the transmission shows what model it is. my guess is this is the 545RFE transmission 4x4, right? got P0706 errors, shift lever , errors? (just a wild useless guess but i'm illustrating why you need to scan it) here are all those connections. which are failing, takes testing.. see the video yet , "how it really works"
https://www.youtube.com/watch?feature=player_detailpage&v=e_xOJCqvi2Y#t=3846min23 seconds into VID, the switch top right below is not where you think it is.id re-seat the big connector and pray....
the driver shifts to drive.the cable moves to drive.the transmission TRS switch lands on Drivethe transmission TCM(in the PCM) tells the PCM you are in DRIVE and the PCM tells the BCM to tell the cluster you are in drive.using the CAN-bus comm network.not like a 1993 at all. not even close.