Problem With Speedo

[W0rp3D]

I have just installed an epson ej1 and nizmo dash with lcd screen, all went well apart from the speedo now says i am doing a little over half the speed im actually doing, i removed my avcr display when i put the dash in which i know was only 2k's out, so i plugged it back in to check the speed and now my avcr is doing the exact same thing.

The only thing i can think that i did wrong was when i wired it up one of the wires, it was not the actual wire off the ecu, there was a wire coming off the ecu wiring going to the avcr so it was easier to just use the avcr wire to tap into, im not even sure if it was actually the speedo wire that i did it with, any idea if this could be the problem, or any other ideas what it could be?

[W0rp3D]

Still need help with this, i have since moved the wire and have fitted another speed sensor in the gearbox but there is no change, is there anything else that the speed signal pass's through before it gets to the ecu that might need replacing?

[89CAL]

This wouldnt cause it to be that far out, and im not sure on the specifics of that dash and the drivline its designed for but ur ratios could be different to wat it was designed for but i dont think this would cause it to be that far out. I know for a fact that the speed sensor goes to the speedo then to the ecu, or they run to the dash and ecu on a seperat system. My speed wire was cut at my ecu so when i got my power fc my speed was always at 0 but my speedo worked fine

i dont supposed thats much help but i thought id just throw it in there. One of the wires that went up to your old dash would be the speed wire yeah? If you could get it on a dyno or even put it on stands or something and put it in gear and let ur foot off the clutch and sorta increase speed a bit and use a multimeter to find the wire with an increasing voltage and use that wire

if using that wire doest work then perhaps theres something wrong with the cluster

have a good christmas and once again i apologise for giving u what may be useless information lol

[W0rp3D]

I have tested the voltage signal at the ecu and i know that is all screwed up, manual said it should go between 1-5votlts i think i was, but it actually goes between 3-12volts.

I assumed that the speedo wire went from the sensor and then was split with one going to the ecu and the other to the cluster, will have to check into the theory that maybe it runs through the cluster then to the ecu, that would explain why the dash (which may have the problem) and then the avcr which is wired after it (assuming it goes through the cluster first) are both reading wrong.

At this point any suggestions are a help.