Need a little advice.
I pulled the cluster to replace a coolant temperature gauge. No problem.
When I went back into the car, the park brake light came on as soon as I plugged it in.This is new,and was not dong this before I pulled the cluster.
When the key is on,the light goes out,and when you pull up on the park brake,it comes on normally.
I pulled the trim off the park brake,and checked the switch. Wiggle tested all the wires under the dash.
After a few hours of fun,I decided to pull the bulb, and go for fixing this another day.
But as I loosened the bulb from the circuit board, I heard a clicking. After a bit, I found there is a relay behind the right lower cluster mounting screw, behind the main dash trim. Sure enough,when I play with the bulb tightening and untightening,it clicks pretty good, and the bulb lights up.
What is that relay, and any idea what the heck is going on?

[This message has been edited by gatorfrey (edited 01-09-2022).]

Dash "sockets" where you plugin big plugs on back likes to have failed "glue" holding copper on plastic "board."
Then copper bends and short out whatever.

Carefully pull the plug(s) and look thru windshield or use mirror or small camera to see the holes to look for bend copper.

see Instrument panel bulb layout https://www.fiero.nl/forum/Forum2/HTML/138175.html

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

[This message has been edited by theogre (edited 01-09-2022).]

Thanks.
Makes sense. I just that whole thing out on the bench.

I will try that.

Just curious though.
In case it matters when I do go back in, what does that relay control?
Laying under the dash,it it not visible, but you can put you hand on it. It is on the center console side, up a few inches above the cluster mounting screw.

Trunk/engine lid relay??? But that should be lower, on the steering column support.
BTW, some helpful Fiero manuals are available here : http://fieroinfo.com/manuals/
so maybe you can find your relay in a service manual ?

[This message has been edited by Rexgirl (edited 01-11-2022).]

Remove the lower panel under steering column and forward panel behind windshield, that will enable you to remove all the cluster connectors so you can carefully inspect each socket with a mirror and flashlight, to make sure nothing on the fragile flexible circuits has corrosion or is bent.

I am not afraid to pull the cluster again.
I just pulled it to replace the temp gauge,as the needle fell off the old one (before I bought it). I am also replacing the gauge sender and harness tomorrow. The plug crumbled away..
A visual check was done when the problem showed up. But from what I could see, it looked normal. I can pull a cluster pretty quick now, so we shall see.
Tach does not work. I saw that the filter is often the issue. Checking that, it looked poorly,so, waiting by the mailbox for one from the Fiero Store.
Once I get all that straight, if I still have an issue, I may just swap out the whole cluster for a different one.
Interesting the relay goes to the deck lid release. That does not work either.

[This message has been edited by gatorfrey (edited 01-11-2022).]

The trunk release was design to only work if the parking brake is applied. That was to prevent opening the trunk while moving.

The relay is part of that circuit.

Thank you,
Another piece of a puzzle.
Strange though. My other 87 GT years ago would open any time I hit the button. I actually rarely used , or use, the park brake.
On inclines or where it made sense,sure. But on level ground, I usually just left it in gear.
I should not recommend that.But it is what I have done for almost 45 years.
I did fix the speedometer issue,coolant temp also. Still waiting on the tach filter to see if that's my issue there.
If the deck release requires the park brake on, I want to bypass that feature like my other Fiero, It was much more practical for me that way.
But thanks for the tip on what that dude does.

As planned, now knowing the gauges themselves are all working, I have ordered a set of white dash overlays, and enought 194 red LEDs to replace all of the instrument cluster and GT secondary gauges in red, and the two tiny bulbs for the ashtrays.
While I am at it, I added the needle paint offered by white gauges, and clear lens polish.
I mean, heck, if I have to pull the cluster again to try and trace the park brake light being on, I am going for it, and snazzing up the dash a little.
The overlays should be here in a day or two. However last night something new happened.
Driving down a smooth street, and suddenly the right turn signal dash light came on steady. Right blinker still functions, so I am assuming a possible further ground/short problem for the cluster ?
I don't mind pulling the cluster again, for this time. But I kinda don't want to have to do this again. Should I replace the film thingie behind the cluster ?

I got a Gentex mirror with home link and compass in red.
I am putting in this week.
Rolling along. But curious if the right turn signal and park brake are electrically related to guide me to something?

quote Originally posted by gatorfrey: I have ordered a set of white dash overlays....

Just a suggestion, do NOT remove the needles from the gauges. Simply pop off the center cap and the gauge faces can slide right over the needles.

[This message has been edited by IMSA GT (edited 01-30-2022).]