1987 C4 Electrical issues
Thread Starter
Heel & Toe
Joined: Nov 2006
Posts: 20
Likes: 0
From: Springfield Missouri
1987 C4 Electrical issues
So my dash lights have gone out. The dash still works (the lines in the digital dash still climb with the speedo and what not) and such but the lighting does not work. also my horn has gone out. What should i go through to diagnose?
Race Director
Joined: Sep 2003
Posts: 16,836
Likes: 337
From: Database Error Indiana
This will help with the dash.http://www.batee.com/corvette/index.shtml
The horn relay is in a fuse block in the area behind the climate control. May or may not help.
The horn relay is in a fuse block in the area behind the climate control. May or may not help.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
First check the 3 amp INST fuse with an ohmeter. If ok, then pull the dash cover off the cluster. You will see 4 bright silver lamp covers, remove them and wrap a piece of masking tape that overlaps and use a needle nose pliers on the overlap to pull the lamp STRAIGHT out and check each one with an ohmeter. To replace the lamp, find a piece of tubing that fits over the lamp loosely and insert the lamp STRAIGHT in. If you turn the lamps, you will turn the socket they sit in and you will have to remove the cluster to put the push-turn socket back in place.
Thread Starter
Heel & Toe
Joined: Nov 2006
Posts: 20
Likes: 0
From: Springfield Missouri
The ignition was in run, and the LCDs read out properly, but the backlighting does not work. I have traced down a wire that runs between the INST fuse and the headlight switch. I might just direct run that on a fuseable dedicated powefeed.
Thread Starter
Heel & Toe
Joined: Nov 2006
Posts: 20
Likes: 0
From: Springfield Missouri
well...I checked the bulbs in the cluster just to see, and sure enough the filiment was sitting right there in the bulb, detached from the two posts. After looking long and hard at the wiring diagram, ive come to the conclusion that the reason the INST fuse is not getting any sort of power is because all 4 bulbs are burnt out and if i replace them the thing will work. If this is not the case, then i guess its time for a dedicated power to the dimmer switch.
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