Speedo not working

Sounds like you need a new speedo cable .... first step is to get a repair manual. If you can remove the cable from the back of the speedo and have someone hold it while you are driving, if you apply light pressure to hold the cable in solidly, and then try to stop the cable from spinning, but not so much that you snap the cable yourself. The cable should spin while the car is moving forward. Once you replace the speedo cable the speedo and odometer should work again, if not it might be the speedo head, which spins the cable. Try to get a manual. Haynes is OK but the factory Honda manual might actually be the most accurate. If I understood this correctly you should be good to go but if you need further assistance feel free to holler back again.If the cable is OK but the speedo still doesn't work it is most likely the speedo guts ... used ones should be available for about $100 or so. The cable should solve your problem hopefully, making further work unnecessary.

What make , model , year an engine size ?

you might want to check the speedo drive gears at the transmission and make sure they are in good shape and the gear that drives the electrical portion is spinning freely as any damage here will cause intermittent speedo operation.also if this is an electrically sent speedo from the tranny check the electrical connections.there is also a speedo buffer in the dash that rarely goes bad but is still a possibility.and lastly it could be the speedometer head thats the problem.when the speedo stops working does the odometer still work.if so then the problem is in the speedo head.i don`t remember which ones or what year they changed them but some you could just replace the speedo head and not the whole cluster assembly.

Check to see if your speedo is electronic or mechanical, If electronic I recommend replacing the sensor in the rear of the pumpkin, If not and its Mechanical replace the gear in the transmission, check and see if the end that goes into the speedo is warn, cable should be replaced...check to see if the cable end is or should be square and matches the hole in the speedo.

If the speedo still works but the odometer doesnt then the speedo needs to be replaced, just replace the cluster,

What is the code that you have? The speed sensor and speedometer is all electrical. So the problem must be electrical. You may have a bad "new" sensor also, it doesn't happen much but sometimes these things don't work out of the box.

try replacing the speed sensors.

Speedo has a loose or broken connection behind the gauge cluster.......Odometer needs to have the gears replaced ( inexpensive part), this part can be sourced on ebay or www.bavauto.com

if the speedo still works then it will need a spedo unit if the speedo doesn't work it is either the cable or the gear in the trans to check the cable unthread from trans and attach a drill to the cable innereds spin the drill if the speedo does not move replace the speedo cable

your fluid is low and quite possible you seized your tranny up apply fluid and dont just rely on dipstick for this make sure the tranny is full of fluid

your linkage to transmission might have come apart another reason for no shifting

now for the speedo
there is a little device that connects speedo cable to the tranny and then the mechanical of tranny from there is called a speedo bullet
if you seized your tranny the speedo bullet would have gotten sheared off in side the speedo bullet is wrenched on and can be wrenched off replace the bullet speedo should start working again