72buickgs

I mentioned, early, in a thread that my grandson just purchased a 1988 Firebird.
Unfortunately, the instrument panel lights do not alight either with just parking lights on nor headlights. The dome light will turn on when u turn the wheel on the switch assembly.
The fuse is are good.
i am guessing that the light switch has failed or there is perhaps a loose connection. I doubt that all the IP lights are burned.
I am 3.5 hrs away from him, so I can not be there to diagnose from your suggestions. I did send his dad a picture of the IP wiring & diag suggestions from the service manual my '84 T/A
Tkx

OrangeBird

iTrader: (1)

The usual culprit for your Grandson's situation is this "remote dimmer unit", which is nothing more than a transistor mounted to a heatsink.

This is a Firebird thing only, Camaros don't have it, and it's located in the area of the "convenience center"

sofakingdom

iTrader: (1)

Yup...

Very common transistor. (or at least, was at one time) Very easy to obtain. Common JEDEC number 2N3055 works perfect. You can get it from MicroCenter or the like, Digikey, Mouser, Jameco, etc. "Universal replacement" line NTE carries it as well, and that's widely available in lots of electronic hobby type stores, such as for robotics.

Clean the heat sink up with lacquer thinner and use a blob of heat sink paste such as for computer CPUs, like you would for the ignition module in a distributor.

John in RI

iTrader: (167)

If ALL the IP backlighting are not working ( Cluster, option button lighting, radio backlighting, and so on... ) then the remote "DIM" module OrangeBird describes is the most likely suspect. ( Check ALL your fuses ! )

If the ONLY the cluster backlighting is the problem than you might very well be looking at a bad trace/circuit on the clusters printed circuit board. This has become a much more common problem over the last 5-10 years as they age. The printed circuit will peel apart (or the layers of the printed circuit will separate) causing a lack of contact and the loss of function.

Just something that *might* help trace the cause of your problem,... good luck !

OrangeBird

iTrader: (1)

Great info John

When I saw the OP's mention of "Instrument panel" my mind read that as "Dashboard" and I thought he was talking about the whole shebang. If as you say it's only the gauges themselves out and the other dashboard lights work (HVAC, Radio, etc) then yeah, it wouldn't be the transistor.

So, we now await the OP's answer of how many of the lights controlled by the thumbwheel are actually out

John in RI

iTrader: (167)

When I read ""Instrument panel" in his post I wasn't sure exactly what he meant to describe,... so I just wanted to cover both possibilities !!

72Buicks ---> Be sure to check that INST fuse !

72buickgs

Problem solved.
Message from my son-
Thanks yes I saw what you passed along from the Third Gen forum.

In short, we got the IP lights to work. Involved digging DEEP under the dash to extract the dimmer unit. We took it apart, cleaned all the contacts and put it back with new thermal paste and bingo back in business.

It was brutal getting access to it (had to dismantle brackets and move wiring aside). "Convenience Center"? More like "inconvenience center"! If Alex needs to replace the signal flasher unit (it resides under that area of the dash just not as deep) it'll be a pain but at least he's torn into it once so he'll know what to do next time.

Say thx from the 3rdgen guys!

John in RI

iTrader: (167)

SWEEEEEET !!!!!!!

T.L.

I've never had any trouble accessing the convenience center in my '83.
'Glad it was something simple.