Cluster lights dim, turn and high beam indicators on

[demian5]

Help
On my 70 gmc, I have an intermittent issue.
The cluster lights go dim (all except the one on the far right of the gas gauge). When this happens, both torn sugnsl indicators are lit dim as well as the high beam indicator. If I turn the high beams on, the cluster lights all but turn off they go so dim. I would wiggle the headlight harness and just stuff in general and they would all be fine again. I feel it's a ground issue or the printed circuit board but what grounds are for the cluster? Any help or insight is appreciated!
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[67 chevelle]

Try running a jumper wire from the printed board to the metal dash for ground

[demian5]

Originally Posted by 67 chevelle

Try running a jumper wire from the printed board to the metal dash for ground

I was thinking that was my first plan of attack. I appreciate the confirmation.

[demian5]

SOLVED - I added a ground wire from the back of the cluster board bolt to the chassis. No more issues.

[custom10nut]

Originally Posted by demian5

SOLVED - I added a ground wire from the back of the cluster board bolt to the chassis. No more issues.

When you say "back of the rhe cluster board bolt", what do you mean. I have the same exact issue with mine. I went and bought a new printed circuit, thinking that was the problem.

[VetteVet]

Originally Posted by custom10nut

When you say "back of the rhe cluster board bolt", what do you mean. I have the same exact issue with mine. I went and bought a new printed circuit, thinking that was the problem.

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There are small sheet metal screws around the perimeter of the cluster that will work as grounding points. You can use any one of those that is convenient.
There are also some in the circuit board that hold it to the metal tin which are grounded to the metal as well.

see this picture.





and this one shows how to wire in a voltmeter in place of the battery gauge. The purple wire is the ground side of the voltmeter and it is connected to one of the screws that could be used.



There is also a ground wire that goes to the cluster plug to pin 7 if I recall correctly, which if it had a poor connection, would result in the symptoms described by the original poster, where he could jiggle the wiring harness and get the lights to work.

[demian5]

Originally Posted by custom10nut

When you say "back of the rhe cluster board bolt", what do you mean. I have the same exact issue with mine. I went and bought a new printed circuit, thinking that was the problem.

In the picture in VetteVet's post, it was the screw above the speedo and to the right of the upper illumination bulb. It was loose already. I plan on putting a spade terminal there so in case I have to remove the cluster, I can just pop it off.

[custom10nut]

Well I answered my own question when I took my dash out. It wasn't a ground issue, though I do thank those for the responses, because now I understand.
When I was fiddling with adjusting the tach, I screwed up my printed circuit to the point it was FUBAR. Right now I have my dash sitting on my coffee table with a brand new printed circuit. As an added measure, I'm going to put the additional ground on, because we all know how these trucks love grounds.