I've recently bought a 740 turbo and the fuel gauge didn't work. We took the instrament cluster off and inspected it ( forgeting to take the batt cable off) all looked good so a reconected it . Now none of the gauges work .... I resently replaced a part of the coolent system (not sure what it was called ) but it had a hollow wire conected to it, shortly after I noticed my temp gauge started working. But only sometimes... What I'm more worried about now is the mph batt and rpm gauges ... What could I have done ?? Btw when we took out the gauges all the dummy lights when I turned my key on stopped working all of them but the seatbelt one ......

 

Well, a couple of possibilities. Most obvious is the chance you didn't connect the cluster cables correctly. They are difficult when the o.e. keepers are not present to assure correct fitment. Second would be a loose or bad common ground that was loosened further when the cables were tugged on removing the cluster. As for the fuel gauge, often the issue is at the other end. The fuel level sender works on resistance. If you take the sender wire off and ground it to chassis, the gauge should read either totally full, or totally empty. If you get needle movement, you can presume the gauge is not the issue but rather the intank sender itself. You'll find lots of good stuff here...http://www.swedishbricks.net/700900FAQ/FAQSummary1.html

 

A few things. I think one or more of the long plugs in the back is offset a little so give you funny signals or none at all to the gauge cluster, like swift thinks and like I talked a little about in your other thread. But I do have a few other things to note.

If the gauges are plugged in correctly and the temp gauge is still acting funny, it can be these things too:

Mine right now has a weak connection to the printed circuit on the back. Mostly in cold weather the gauge won't work unless I firmly tap the dash and then it works like a charm for the rest of the day. I don't think that's likely, but these dashes are known to have weak connections because of the printed circuits. Most of the time you just need to tighten the connecting screws to fix it.

A few years ago, my temp gauge would bounce around a bunch and most of the time not register anything at all. It was schizophrenic. I got a new sender for like a buck at a wrecking yard and it's never done that since.

However, as long as you have widespread failure of gauges in the cluster, it would seem to be something in common with them all, like a plug in the back.

Also, my car is the same year and model, I have all the green books for that car. I can make a copy of the wiring diagram for the car if you think that will help. But if you think that's excessive and won't help you, I won't bother since I have hard copies and not electronic copies. It would take a while to scan them all in. Plus, I don't know if that is what Swift PMed you.

 

I don't really have time to wright everything right now but thank you both I'll look into all of it