HI I have two separate issues. I may have just fixed one. The van has been in limp mode for 6 months and I drive it lightly around town and every so often it shifts correctly in the middle of an errand, but the next time I start it, it is back in limp mode. Then I developed this crank but no fire issue about a month ago that got progessively worse until it would die after two to three miles and role to a stop. It would crank, but not start for a varying number of hours, but always would start the next day. In a post of three days ago I talked more about that issue. The Dodge dealer could find nothing to fix, so I went to pick it up today, and sure enough, 2.6 miles into the drive home, it died and I called for a tow home. I put in a new crank sensor, and now I have driven it for 10 miles in circles staying close to home and it seems that this may be the fix.
On to the limp mode issue. I have changed the TCM, the PCM, the input and output speed sensors, the O2 sensor, the cam sensor, the crank sensor, the solenoid pack, and I am probably forgetting something, but I think it is in limp mode because of a wiring harness problem somewhere. I have read numerous posts about this splice of three wires to one or something, and I want to get into the harness at somewhere close to this splice. Any suggestions?

Yup. I remember several threads talking to this magical splice but none recently. As I recall the location was never revealed. I do recall some talk about a wire harness running under or near the battery that can corrode and create headaches. Unfortunately I don't remember if it was causing limp modes or not. This harness is still worth a look. Only other thing I can suggest is to head over to Chryslerminivan.net and see if they have any info on the splice.

This website is loaded with info on your transmission:http://www.robskorner.org/faqs/Trans/a604miscinfopg.html