dash lights in my 86
09-25-2001, 04:09 PM
#1
Team Owner
Thread Starter
Member Since: Sep 2001
Location: Athens AL
Posts: 59,654
Received 1,401 Likes
on
1,017 Posts
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
dash lights in my 86
Ok, heres the deal, The light bulbs in my digital cluster dont work. The one under the speedo comes on when i crank her but when i hit a good bump it goes out. The display shows the numbers fine, it just doesnt light up so i can see it better (this also means that at night, i have NO idea how fast i'm goin or what temps i'm running). Ive decided to order the replacement bulbs but i was wondering if it could possibly be anything else. Also, when i put the new bulbs in, should i do anything else while i'm in there? (i know to NOT touch the bulbs bc of skin oils) thanks
09-25-2001, 04:40 PM
#2
Re: dash lights in my 86 (vader86)
Just get the sylvania 882 from pep boys, kragen or another chain-lot less $$ than a dealer. If everything else is working on the dash-nothing else to do while you're in there. Just be carefull not to crack the lcd!! Its the outer glass part. I put a thick rag across it when I take it out.
09-25-2001, 04:47 PM
#3
Racer
Member Since: Sep 2000
Location: Princeton Texas
Posts: 294
Likes: 0
Received 0 Likes
on
0 Posts
Re: dash lights in my 86 (vader86)
The bulbs are available from any discount auto store. (Sorry, I can't remember the bulb number but it was on one of the bulbs I removed) They are bayonet style, and plug into the part that twist-locks into the PC board. There is an onboard regulator for these bulbs and also a separate fuse in the fuse panel. Make sure the contacts are clean before installing the twist-lock assemblies back into the PC board. It is also advisable to handle the PC board carefully and observe ESD practices by grounding yourself while handling the PC board. Electro Static Discharge can easily damage many of the components on the PC board.
FP
FP
09-26-2001, 02:08 AM
#4
Team Owner
Member Since: Mar 2001
Location: Cincinnati, Oh USA
Posts: 53,930
Likes: 0
Received 26 Likes
on
23 Posts
Re: dash lights in my 86 (vader86)
Considering the age of your C4, you most likely have an unsoldered pin on the lower circuit board that carries the current to the lamps. This is caused by an age relaxed spring on the socket for that pin which increases the connection resistance and makes heat from the lamp current which further aggrevates the situation until it gets so hot it unsolders the pin. The pin is closest to the center of the board. Resoldering is not a fix. You can replace the socket and resolder the pin, but I soldered a small #24 jumper wire between the pin and socket and that can no longer happen. There is a single row of pins that connect the two circuit boards. See http://www.@umr.edu for info on board removal and repair.
