Electrical Problem
Thread Starter
Melting Slicks
Joined: Sep 2003
Posts: 3,326
Likes: 1
From: I live at www.domesticlugnuts.com I sleep in PA
Electrical Problem
My 84 Digital Dash has become possessed. When I start the car, I can drive several miles and all is well. Then the Tach will start flickering all the light bars showing RPM's that are not true. Then it will move across the dash to the center display and start lighting all the LEDs at once and then finally it will get to the Speed section and do the same. By this time every LED in the Digital Dash is Flickering on and off randomly. If I shut the engine off and coast with the key on the display is 100% correct. As soon as I start the engine it all starts going wild again. This started on the way back from Carlisle and has gotten worse.
Is this the "Ground Problem" that I have seen posted here. And if so...What is the fix? BTW my alternator is putting out 14.4 volts at startup and drops to 13.9 volts after a few minutes as always. Any help or advice would be appreciated.
Is this the "Ground Problem" that I have seen posted here. And if so...What is the fix? BTW my alternator is putting out 14.4 volts at startup and drops to 13.9 volts after a few minutes as always. Any help or advice would be appreciated.
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
There are several grounds to the digital dash... The ambient sensor is the one most have trouble with. You can bypass that by just running a second ground from the ambient temp sensor on the drivers side firewall behind the hush panel. The other ground is on the drivers' side door pillar. This one is more related to the DIC though. You could start there...
Thread Starter
Melting Slicks
Joined: Sep 2003
Posts: 3,326
Likes: 1
From: I live at www.domesticlugnuts.com I sleep in PA
I looked around and found a ground wire that was loose coming out of the firewall going to the back of the head and I tightened that. The problem seems to start about 10 minutes after you start the car. I disconected the alternator, just to be sure it was not spiking voltage and the problem still persist. What I don't quite understand is, if it is a ground wire and I'm driving around 70mph and turn the engine off and let it coast. When I turn the key back on, shouldn't the flicker still be there (The road was not that smooth). It does not reappear until I restart the engine. It has me a little bit confused.
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
In my cluster the power supply was fried. The cluster would turn on when i'd start the car, but would eventually start flickering, restart a few times, then go black. In my case I think the alternator killed it cause i was overcharging way too much... if i understand how the cluster works, it initially charges and resets itself when you turn the car on... it might be slowly losing power as you drive, only recharging once you restart... of course this is just my guess. My cluster has been driving me insane since i got my vette. I've checked every ground. Sent my cluster away to be repaired- they cleaned it up and replaced the power supply. Got it back, and it worked great for a while. Now its out again. In that brief time it worked, I saw the alternator was overcharging badly, I got killebrew's book, and it mentioned that could kill the dash. So now, with an new alternator, i'll send the cluster back to be repaired.
Large Impressive Member
Joined: Jul 2003
Posts: 65,811
Likes: 71
From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by Rich & Lisa_84
My 84 Digital Dash has become possessed.
Racer
Joined: Feb 2004
Posts: 265
Likes: 1
From: Irwindale Ca
For what its worth. I took my cluster apart and inspected two rows of one inch spikes. They are basically connections when the assembly is sandwiched together. I noticed two spikes were burned at the base. Basically a open circuit between the two points. I placed a piece of 10 gauge wire as a bypass to connect the two points and I have never had a problem with my gauges. 
