The dash lights on my 1990 ZR-1 are usually too dim. It’s hard to see the instrument panel in many situations. For example, when the car is in the garage, the dash lights dim to off. When I’m driving in the sunshine, the dash is readable but not bright.

There are a number of threads asking about this problem
Eg,
https://www.corvetteforum.com/forums...ent-panel.html
https://www.corvetteforum.com/forums...rd-to-see.html

A common response is to replace the dash bulbs. This isn’t the problem in my case. I tested every bulb, but I went ahead replaced every dash bulb also. All of the bulbs work fine.

When I first start the Z, the dash is very bright during the “test” but then dims down. When I turn on the lights, the dash will brighten up as it should. The connectors are seated fine, and the grounds have been cleaned and tested. The polarizing film is fine as I can read the black LCD segments fine.

When the lights are on, I can use the dimmer to increase and decrease the brightness of the dash lights.

When I shine a light onto the photocell, the dash lights brighten up.

I still suspected a problem with the photocell. There are no specs on the photocell however, and no markings on it that would help me find a replacement. I bought a different DIC with the photocell and installed that. The lights are a little brighter (as measured by my light meter), but I still don’t think it is bright enough.

As I have an aftermarket head unit, I wondered if the common “resistor” fix for the headunit (throws a SYS on dash without it, although my install never did) would affect it. I added the resistors and still the lights are dim.

So … does anyone have any ideas?

TIA,

Gary

 

Hi

http://www.batee.com/

He is the guru with early and late c4 instrument clusters, have a good look at his webpage for common issues that you can easilly repair yourself, or get it repaired for you.

He also has many common failure repair kits on ebay

 

Thanks. I know of batee and used the site to fix my 85. I don't see anything there that addresses the problem on my 90 though.

 

Have you looked at the dimmer switch?

 

Yes. The dimmer works. It does increase and decrease the brightness of the dash when the lights are on.

 

Batee's 90-96 Dimmer Circuit Repair Kit may be just what you are looking for. Here's the jump: http://www.batee.com/corvette/dcrg/s...photocell.html
There are even instructions with pictures to do the installation.

 

Well, dang, I obviously missed this, didn't I?

You guys are right, this could be the solution. I'll order the photocell and get it installed.

Thanks