Chrysler Repair: Intermitent Speedometer Malfunction, 1992 chrysler lebaron, chrysler lebaron

Question
I have a 1992 Chrysler LeBaron Convertable with the 3.0L V-6 and automatic tranny.  I have experienced an intermitent speedometer malfunction since I got it.  When I replaced the speed sensor on the new tranny, it did not rectify the issue.  Sometimes it will stop working after I have been driving for a while, Most of the time it works all the time, sometimes I have to accelerate quickly to about 30-40 MPH before it will kick in.  Do you have any clue?  

Answer
Hi Lee,
I would say it is an electronic problem except for the fact that you say you can get it to respond by accelerating. That may imply that there is some issue of the gear interconnection with the right side half shaft spline. I suspect that the only way to know for sure is to monitor the signal from the sensor to see if it drops out when the speedo drops out. If not, then the speedo head unit would be suspect.
If you have mechanical cluster, the signal comes to the cluster on pin 5 of the black connector on an orange/white wire. If you had an ohmmeter you might put a tap on the wire and observe the signal for any change when the speedo stops working. If it does, then you can trace the wire thru the firewall bulkhead (position 42) through a 10 pin gray color disconnect behind the battery, to the black 2-pin disconnect near the sensor and see where the drop out is occuring. If the signal doesn't change when the speedo drops out then the problem is the speedo head unit.
If you have the electronic cluster the speedo signal comes from the engine controller via the data bus so you would need to make sure that the signal from the sensor is getting to the controller pin 47 where it is added to the data bus. There is no way of easily reading the data bus without a diagnostic readout box.
So unfortunately there is no simple answer to your problem. But the above will tell you what the problem is.
Roland