I need some help. My HUD in my 1999 grand prix gt will go dim and bright as it pleases and occasionally it won't be there at all. Can anyone help with the problem?

This should help you out with the fix .....~Larry~


How to fix the HUD dimming problem.
By Steve Cox, ClubGP Member:1890
9/22/2001

1. Remove HUD from car.
2. Remove 4 Torix screws from top of HUD
3. Remove ribbon cable and small 2-wire cable from circuit board.
4. Remove circuit board.
5. On the board there is a small photocell, the problem is that the cell has a cold solder joint. The cell is a 1/3-inch
Circle with a black square in the center. All you need to do is resolder the two legs.
6. Put everything back.

I was unable to find a replacement cell at radio shack. Monday I will look at a Digikey catalog and try to find the part.
The cell produces a small amount of voltage. The more light the more voltage. 0-.75 volts. Mt cell was working fine but the joint was loose. When the board heated up it lost the joint increased resistance to the point that the HUD lost the voltage reference.

So far this has worked for 4 hours. Before the fix it would dim out in 10 minutes. I need others to try this and report back.

http://www.seacgp.org/images/hudfiximage1.jpg

http://www.seacgp.org/images/hudfiximage2.jpg

Good Question. I have a 00 that does the exact same thing. Seems to do it more often when its cold outside. Eventually I guess I'll have the dealer replace it before the warranty expires.
Except now that I see the post directly above mine, I will try that first.
Thanks Big-L! :naughty: