Help!

I am only getting instrument cluster lighting on the right side of the display. Also, my tach is not working (I've tried by passing the tach filter) as well as fuel and temp gauges are not working. Speedometer and auxiliary gauges above the a/c vents are fine.

When I turn on the parking and/or the headlights, the temp gauge jumps all the way to the LEFT!

Everything was working fine when I purchased the car a year ago. Things went south after I redid the interior, but I've lived with it. Now that we are staying home, I have the time to try to fix it. I've taken the covers off to see if there was a wiring plug either not inserted all the way or not at all, but I don't see anything obvious. Fuses all look good. The printed circuit on the back of the cluster seems to be intact, but I can't be sure. Could I be missing a ground somewhere? Are the dash lights separated/divided somehow? Seems really odd that just half of them would be out. And if I wasn't getting power to the temp gauge, why would it jump to the left when I turn on the lights?

Any ideas?

Thanks!

Check the fingers on the flexible circuit board that make contact with the plug. It's not uncommon for the fingers to delaminate from the substrate and cross over each other, causing all kinds of goofiness.

If they are delaminated, they can be re-secured with some adhesive.

quote Originally posted by olejoedad: Check the fingers on the flexible circuit board that make contact with the plug. It's not uncommon for the fingers to delaminate from the substrate and cross over each other, causing all kinds of goofiness. If they are delaminated, they can be re-secured with some adhesive.

Are you talking about the harness on the bottom left of the cluster? I've pulled that and it doesn't seem to make any difference whether it's connected or not. What do those wires do? (I haven't pulled the plug on the right side yet)

Thanks for your help, I'm definitely not a wiring guy!

Bottom left is for the speedo only.
There are two plugs on the back (actually front) of the cluster.
Remove the cluster and look at the tabs.

I agree. You should remove your gauge cluster and look at the female connectors. That's where I would start. Some of the contacts might be bridged or dead.

The reason why you're not getting any lighting is most likely because your light bulbs connections are not making contact with the circuit. I was having some trouble with one of them. You can try to bend the contacts towards the circuit which should help. If that doesn't, try looking for replacement light bulb sockets. They're common enough in the junkyard.

Before removing the dash or big plugs to it... (Big back plug(s) w/ problems doesn't just = 1 or 2 bulbs w/o power.)
Wiggle or Remove Lamp sockets. Also see https://www.fiero.nl/forum/Forum2/HTML/138175.html

Sockets can break so can see easy but metal parts in the sockets can break/crack and often hard to see. Plus Dash plastic and "board" can compress/warp at the contact point where socket hits, etc.
Example: Sometimes can rotate a socket so socket ears get better contact pressure on the board.

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Well, I did all the above: After removing the cluster I examined the printed circuit, cleaned all the "fingers" and bulb connections, checked that the plugs were all inserted properly and tight, and there was no change. I still only have the right side lighting, no tach, and no fuel or temp readings.

What can I look at now?

On a side note, when removing the cluster I found a grey plastic female plug with 5 wires going into it under the shroud on the right side. I couldn't find anything that looked like it should plug into. What is that? I can post a picture tomorrow if needed.

Thanks!

quote Originally posted by Habanera Hal: Well, I did all the above: After removing the cluster I examined the printed circuit, cleaned all the "fingers" and bulb connections, checked that the plugs were all inserted properly and tight, and there was no change. I still only have the right side lighting, no tach, and no fuel or temp readings. What can I look at now? On a side note, when removing the cluster I found a grey plastic female plug with 5 wires going into it under the shroud on the right side. I couldn't find anything that looked like it should plug into. What is that? I can post a picture tomorrow if needed. Thanks!

Next I would check and make sure that you are actually getting a signal from the car to the gauges. So using a volt meter you want to check if you're getting a reading for your tach, lights, fuel and temp gauges, etc. If you are getting signals at the connectors, the gauge cluster is the problem. If you are not getting signals, you will have to do some more digging to figure out why.



Is the the plug? If yes, my gray connector has four wires and goes to the trunk release. My black connector has five wires and goes to the defroster.

quote Originally posted by rbell2915: Is the the plug? If yes, my gray connector has four wires and goes to the trunk release. My black connector has five wires and goes to the defroster.

That would make sense as my car is a Formula with neither rear defroster or trunk release.

I'll try to find a different cluster to plug in to test when I can.

Thanks for the help!