This is a somewhat common problem, so the replacement speedometer might have the same problem.

If you have done PCB work, then you may be able to fix the original speedometer. You can take apart the cluster. On the back of the speedometer, there is a small PCB board. If you know how to redo solder connections, try repairing any solder joints you can access. If you attempt, would you take some pics, so we can make a DIY? Trying to explain how to do this is difficult without pics.

To see how to take apart the cluster, go to the common diy thread on top of this forum. Open the online shop manuals link. The honda-tech link has a 94 shop manual that you can download. You can inspect the connector for the speedometer.

You have another option. You can send your original speedometer for repair. I mailed my speedometer to powls speedometer service that I found on the web when I had the same exact problem. I think they charged $120 + shipping. They were really fast and the problem never returned for the 4 years that I had the car after their repair. I'm sure that you can find other places that will do the repair as well.

 

No success yet. Going to dealer on Thursday, will report their second diagnosis when
they are finished.

 

The orange wire is the "key" here. As TX said, there is a split some where between the orange wire from the VSS that goes to the ECM, TCU and cruise (why the cruise works and no CEL or TCU code) and then the other side goes to C12 of the cluster

Personally, rare a wire issue after that split would happen. Common, would be the circut board.

PLEASE let us know what you find.

 

Just as a follow up on Poormans suggestions. I did a continuity test of the orange and yellow wires from the vss. The yellow tests good to the firewall and the orange tests good up to the firewall and then up to the back of the gauge cluster at the 16pin. Thanks for the diagrams by the way, big help. I called an online gauge rebuilder and they said the " stuck on 20mph" is a very common problem and I need a new rebuilt speedo. Sooo as some others have advised me on the list already that is where it stands now. But first I need to try an exchange unit from the breaker yard cause they said thats all they can do for me cause I am past the 30 day
warentee. The dash is still a part so thats not a big deal at this point I guess. $160. for a used cluster gear that may or may not work when I could have had my original speedo rebuilt and other gauges tested for $160. with a one year warantee.
Wish I knew then what I know now. Thanks for all the assistance. We'll follow up.

 

Thanks for the update, let us know how it turns out...

 

Hey, sorry for the thread resurrection but this is THE BEST thread I could find as far as relevance to my 95 Honda accord EX that has this exact problem with the speedo stuck at 20mph 99.9% of the time and the odo/trip not working when the speedo is stuck and the cruise works flawlessly so I know the sensor is good. I also have had apart and checked my speedo and it seems to be fine so I wanted to test the orange wire (pin16) to see if the signal is reaching the speedo in the first place or if I have a break in the orange wire after the split as you have described. The thing is I don't know what the voltage should be for this wire with the key on and the car not running.... An answer would be MUCH appreciated.

 

This is a problem with the speedometer, because I had the exact same problem on my 95 accord. Sending the speedometer to a repair shop permanently fixed the problem.

I'm not sure what they did to repair the speedometer. I have read threads where repairing the solder joints has fixed the problem on the small board of the speedometer. There are other posts talking about corrosion/bad connection where the speedometer connects to the main board.

 

Actually your assumption of resoldering is apparently SPOT ON!! XD

I just searched around and found this
http://honda-tech.com/showthread.php?t=2087284
and did it.... just touched the tip of the hot iron to all the solder on the board, both the main board and the speedo one to remelt it all (resoldering) and BINGO!!! Put the cluster back in and it works PERFECT!! OMG I'm so happy with myself now XD

 

Nice to know it worked. The original thread never had a post with the final result, so THANK YOU for letting us know.