Speedo Problems

[dwalker151]

I've got a question guys:



If your speedometer doesn't work and you've changed the speed sensor down on the transfer case what's the next place to look for problems????



Thanks

Dean

 

[Paychk]

Did you check the gear box assy the drives the sensor? Mine was stripped out inside and I used a little JB weld to snug things up again. You can verify this by driving the sensor with a drill motor and with the key in the run position you should get a reading from it. If not that, it is time to chase wires. Oh what fun!



Good luck!

 

[BushWakr - RIP]

dwalker,



paychk is right. The most common cause of this is the speedo gear assembly. I'm having probs with mine right now too. (I think that is what it is)

Be sure that when you take the speedo gear assembly out you make sure to mark it's positon so you can put it (or new one) back in the same position. There is a an external lock ring which will have a couple sets of numbers on the plastic ring. These are so that the speedo know's which set of rear end gears you are using.

Maybe I can scan in a pic and post it for you. .



Bob.

 

[farmall]

On my 92' the same thing happened. I replaced the speed sensor, mine was cracked anyhow. Verified the gear was turning. The speedometer would sometimes jump from zero to actual speed for about 5 seconds and then die again. This would happen far and few between. I noticed though when it did happen it always followed immediately after I used my left turn signal. Anyways to make a long story short, it turned out to be the computer. A circut burnt out and caused my speedometer quit working, my alternator to go to max charge output, my cruise to quit, my wait to start light to quit. A new computer at the Dodge dealer is $798. 00. I got mine at Autozone for $180. Bill

 

[HoofinSoot]

Interestingly enough, my '92 is exhibiting similar symptoms right now. EXCEPT - mine either flat out doesn't work, and sits at zero, or it rotates in conjuction with engine RPM - ala a tach !!! I haven't been able to figure out if it works like a tach after I use another device (turn signal, etc. ), but I will start paying more attention. I sure hope it's not the computer. $180 is the cash I need for my gauges !!!

 

[Slough]

ecm

HoofinSoot

Where did you get your ECM?? speedo, tach, OD, ac clutch, alt quit, sometime I move the ecm and they come back on. other time they will come back on in a mile or to. :{

 

[rkubicki]

There is a grease fitting on the bottom of the speed sensor drive adapter... This is the right-angle drive that comes from the side of the transmission and has the speed sensor attached to the end... When my speedo was acting up, I greased the adapter at the fitting and the problems went away.



I noticed this adapter had a white ash-like substance on it and was very-very hot... . Seems the adapter was not being lubricated enough and the added friction was preventing the sensor from being turned freely.



This may or may not be your problem but it would be a cheap and quick place to start your diagnosis.



good luck!



Rob