NSW Corvettes

Technical Tips => Post 84 => Topic started by: Low59 on March 03, 2004, 08:00:23 PM

Title: 85 LCD display problem
Post by: Low59 on March 03, 2004, 08:00:23 PM

Hi There,
I am new to this forum, and I am seeking some assistance with a problem in my girls vette. The LCD display has lost control of the brilliance. It remains very dim and the volt/oil pressure display alternates irrespective of the switch position. I have been told by an auto elec that ther is a voltage regulator for the display, but I don't know if it is internal or external. Any ideas? Does any one know where I could get it tested?

Title: 85 LCD display problem
Post by: 77CVT on March 04, 2004, 09:43:35 AM

No difinitive answer but check the 4 bulbs in the unit - if one is blown/shorting this can cause problems.  They are behind a round silver clips on the front of the unit.  No need to take the dash out just the front fascia panel.

Title: 85 LCD display problem
Post by: Vette Obsessed on March 05, 2004, 12:48:36 AM

I agree with Chris - check the bulbs first.

Title: 85 LCD display problem
Post by: ben73 on March 05, 2004, 08:37:30 PM

If the bulbs are blown, be sure to use the correct type!  I have repaired these instrument clusters where someone has used cheaper higher wattage bulbs.  They melt the connector between the two main boards and lift tracks off the pcb ect.. It gets ugly..    Alternatively, you can swap out the little lampholders to a different type and use the '194' bulbs as found in the center info display.  They won't last as long,  but they are a fraction of the cost!  The other likely spot for yur trouble is the ldr that chnages the illumination from day to night...

Title: 85 LCD display problem
Post by: Low59 on March 07, 2004, 12:43:51 PM

Thanks guys,
It's nice to get some helpfull suggestions, I have tried other forums that are a little tight lipped unless they know you. My girl sourced this article from a fellow corvette owner in the states. Hopefully it will assist me in solving the problem. I'll let you know. It may be of use to someone else so the address is below.
http://www.corvettemagazine.com/1999/dec99/dash/dashp1.asp

Title: 85 LCD display problem
Post by: Low59 on March 09, 2004, 08:22:51 PM

Back again,
I have used the test procedure that is outlined in the article and it worked a treat. I now know that the display illumination is functioning and the problem is likely to be a bad ground. I'll check on the weekend.