Chrysler Repair: 1999 Plymouth Voyager transmission, plymouth voyager, 1999 plymouth voyager

Question
I have a 1999 Plymouth voyager minivan, and about a week ago while driving home the speedometer quit working and it would not change higher than what seemed like second gear to me.  I am wondering if this could be an electrical or transmission problem.  I had the fluids changed recently, and also about a year ago the rack and pinion completly broke in two and had to be replaced.  It hasnt seemed like the transmission was slipping or anything, just that it will not change into higher gears. I also got a recall notice on a clockspring, and am having that replaced tomorrow.  Could that have anything to do with it?  Many Thanks

Answer
Hi Christy,
The speedo failure may be related to the transmission acting up because both are electronic and have sensors that measure the speed of the car and the speed of the engine. If there is a severe incongruence between the two, then the transmission will go into "limp-in mode" where it stays in second gear so as to avoid damage. So I would seek to get the speedo fixed first and then see if the transmission goes back to normal. I just had a question about the speedo from someone whose speedo had also failed and here is my response:
"The speedometer is electronic in that there is a distance sensor mounted on the top of the transaxle housing (the part of the powertrain out of which the half axles extend.
It is held in place by a single bolt and can be tested by disconnecting the plug near by to it in the wire that runs to the engine controller. If you place an ohmmeter across the two pins of the disconnect you would see 8 pulses in the ohm reading for every full rotation of the the front wheels.
If the disconnect is clean and tight, then I would do the ohm reading, but you would have to jack up the right front wheel and turn it by hand. The sensor has a gear that is driven by the right side halfshaft. It can be damaged if, when the half shaft is removed to service a cv-joint, and the mechanic fails to remove the sensor first, then the gear will be damaged when the halfshaft is pulled out of the housing.
You could also check the engine controller to see if is has recorded a failure to receive the pulses from the sensor. Just turn the ignition key: on-off-on-off-on within a 5 second or less time elapse, and leave it in the on position. Then watch the check engine light to begin flashing, pause, flashing, pause, etc.  Count the numbers of flashes between pauses and note them. If the first two groups of flashes are 1 and 5, then that means the pusles are not being generated or not getting to the controller where the pusle rate is used to generate a signal that runs the speedometer and odometer. The last two flash groups will be 5 in each which means end of code readout. If code 15 is not produced, then that would mean most likely that the speedohead in the dash is broken or the connecting plug is loose behind the dash. If 15 is produced then either the sensor, the disconnect plug or the wire to the engine controller is bad."
So try that readout procedure, though it may have been supplanted by a different technique and code numbering system by 1999 (my expertise as it is runs thru about 1996).
If you find that it works and you get a code 15, then I would expect that the sensor or its gear need to be replaced. You can find it by locating a wire that runs down behind the engine to point down quite low and near the mid line of the body (the top of the transaxle housing). A 10mm head size bolt can be unscrewed and then you can lift out (maybe have to pry a bit around its edge) the sensor and examine its gear.
If when the speedo works the transmission still stays in 'limp in', then you can have the dealer do a fault code readout on the transmission controller (there is no similar do it yourself readout for the trans) which then gives a basis for diagnosing why the trans is acting up.
I don't belive that either of these are related to the clock spring, unless for some reason when the data bus looses contact with the airbag (thru a break in the clockspring wire) this causes a false positive problem being seen by the transmission controller. So play it by ear and don't authorize any major overhaul of the trans (very costly) unless all the other possibilities and code interpretations are followed up to completion.
Roland