Hello I have a 1996 civic ex coupe and the speedometer does not work, everything else does but not my speedo I just replaced the speed sensor on the trans and that didn't fix it, I was going to check the plug to see if its getting electricity through it but don't have a tester, I replaced the whole cluster as well, what other reasons could it be not reading the speed.

 

You have a break in the signal! you need to find where your loosing the signal. Look at the plug itself and inspect it for any cuts or breaks! Also make sure the prongs are making full contact when the plug is plugged in the speed sensor.

 

The signal is a square wave so a regular volt ohm meter will not work beyond continuity testing of the wire(s).

Very often the circuit board on the back of the speedometer goes bad. It is possible you got a cluster with a bad board and saw no change when you swapped them out. But first you need to rule out a break or short in the wires.