73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Interior & Equipment => Instrumentation => Topic started by: Boxchevrolet on March 29, 2015, 01:44:59 pm
-
hello i just bought a 83 chevy k10 with a 350 and dual rear tanks. the fuel gauge works when i start the truck but when i turn on the headlights it drops below empty. can anybody tell me what causes this?
-
Start tracing wires, you have a short somewhere.
-
Loose cluster ground?
From orbit on my Android.
-
While researching that very same problem with my 1985 I found this site. Mine turned out to be a bad plastic circuit board on the back of the speedometer. I went to a pick and pull and found a replacement cluster, worked like a charm..
-
Zieg I was thinking something along that line. I was thinking the dash bulbs were back feeding into the fuel gauge somehow. But couldn't think how
-
My first thought was a burn circuit on the board..
-
To further explain the issue I had, when I dimmed the dash lights all the way down with the headlights on the gas gauge would return to working fine. I could not visually find a burnt spot but a new cluster fixed it right up. I even found one with a quartz clock and took the additional wiring while I was at it.
-
i was wondering if you could "control" the fuel gauge like that. would it slowly rise to the fuel level in relationship with the dimmer level?
-
i was wondering if you could "control" the fuel gauge like that. would it slowly rise to the fuel level in relationship with the dimmer level?
Yes, the gauge was accurate with the lights off or park lights/headlights on, all the way dimmed. Gave the knob a twist and the gauge went to empty slowly based on how bright the dash lights were at.
-
be a nice trick to pull of someone when you want to be stuck and out of gas way out in the woods ;)
and that trick could be played on anyone lol
-
be a nice trick to pull of someone when you want to be stuck and out of gas way out in the woods ;)
and that trick could be played on anyone lol
How did I not know where this was headed...
-
(http://www.naioa.com/v2/modules/Forums/images/smiles/eusa_whistle.gif)
-
well i replaced the circuit board and the fuel guage still goes below e when i turn on the headlights, now I'm looking for a short or bad ground
-
Loose cluster ground?
Agreed. There is a poor connection in the I/P or cab ground path. Clean all of the ground connections from the cluster connector all the way out to the battery. Verify that all of the factory grounds are in place and making good contact (this means taking them apart, burnishing the terminals and attaching points, and reinstalling so they are tight): battery-to-engine, battery-to-right frame rail, battery-to-radiator support, back of right cylinder head-to-cab, I/P-to-cab above e-brake pedal.
-
Also the cluster pigtail
-
^ look for a black wire pushed back in the connector at the cluster
Sent from my iPhone using Tapatalk
-
i still haven't found the issue, I've traced every ground and they are all in place and making good contact, any other ideas?
-
While researching that very same problem with my 1985 I found this site. Mine turned out to be a bad plastic circuit board on the back of the speedometer. I went to a pick and pull and found a replacement cluster, worked like a charm..
That exact same thing happened to me, as well. The problem (for me, anyway.) was one of the dash light bulbs had melted its hole in the cluster. My constantly trying to get it to tighten up tore up the printed circuit that fed power to it, and it eventually caused a short.
Mine, however, blew the fuse for the instrument cluster whenever I turned on the lights.
-
i still haven't found the issue, I've traced every ground and they are all in place and making good contact, any other ideas?
Do this:
Connect a voltmeter, attaching the positive lead to shiny bare metal on the cab and the negative lead directly to the battery negative terminal. Have a helper turn on the windshield wipers, dome lamp, etc. Is there any voltage reading greater than zero?