Chrysler Repair: electronic trans, not shifting, no speedo/odo reading, chrysler vehicle, turbine speed

Question
engine starts and runs fine, the van is not shifting(locked in maybe 2 or 3 gear) there is no reading on the odometer or speedometer. something simple? or is tranny fried.

Answer
Hi Alan,
The coincidence of the loss of the speedo/odo and the trans locking in 2nd (which is called limp-in mode because it allows the trans to be driven without further/any damage) is hopeful for a pretty easy fix. The speedo/odo and the trans both depend upon the same sensor for data in order to operate properly, and that is the output speed sensor on the transmission. This is a unit that screws into a threaded hole in the housing of the trans and has an electrical plug connected to it. It is found on the side of the trans that also has a square box closer to the front of the trans and a vertical rod that is attached to the shifter cable that changes the operational gear settings. If you look toward the rear of the trans from the vertical shifting rod you will see the sensor at about the midline of the housing height. Another sensor that looks similar is at the other end of the trans near the bell housing (that is the input turbine speed sensor). If the output speed sensor is bad or the plug is unplugged (unlikely) then the pulsing signal from the sensor is not sent to the trans controller or the speedo/odo. So I would suggest that you buy a new sensor and then simply unplug the old one by gently lifting the tab and pulling out, unscrew it, and then substitute the new sensor and reattach the plug. That should solve your problem.
Roland
P.S. you didn't mention the year of your Chrysler vehicle but what I have described is applicable to post-'94 model years. In '94 and earlier there were separate sensors for the speedo/odo and the trans controller and so it is unlikely that both would fail coincidentally.