Dash lights malfunctioning

[DubBoomin]

Hello I was wondering if I could get some help with my 78 Datsun 620 with the gauges and lights. 

It started when I wanted to clean up some wiring because the previous owner had some aftermarket stereo or something. But I took all the aftermarket wires off and some of them were like Bridges to the main harness. And I got the lights outside to work but the dash lights are acting weird. So when I barely move the dash the green arrow lights stopped working and the right arrow stays on all the time and sometimes when I move the dash just a little but it turns off. But when all of this happens the left turn signal light stops working, but everything on the outside works it’s just the dash lights. And at times the gas gauge would mark that it’s full and the temp gauge would mark that the car is over heating. And also when I turn the lights on the dash light doesn’t turn on.

 

after all of this I tried to fix it and got it to work but I just moved the dash just a little bit and it stopped working again. So I’m stuck and don’t know what to do. 
 

if anyone can help me out that would be great and would greatly appreciate you. 

[Stoffregen Motorsports]

Check everything you touched and see if there's a loose connection. Sounds like possibly a short, and since it's intermittent, it could be two wires scraping against each other. A bad ground could also act like what you describe. Were any of the wires you removed going to the body or dash?

 

Check the turn signal switch too. Wiggle it around and see if you can duplicate the issue. Lots of older cars/trucks had full power going through the various switches, and when the contacts get old and wear, the continuity goes away.

[datzenmike]

A short would blow the fuse, more likely an intermittent open connection. Ground the dash metal with a jumper wire to a known good ground.

[Stoffregen Motorsports]

Right. What I meant was a jump, as in, two wires contacting each other. Short seemed like the best word, but now it doesn't.

[datzenmike]

I took some electricity in high school and the teacher used to go on and on about what a short is and how when something didn't work it everyone would always say it was a 'short'.  Even in movies by people that should know better. He would connect a wire across a car battery and it would light up like a toaster. "That's a short" he would say.

[iceman510]

The weird behaviors suggest bad ground, as circuits are going through other circuits to find a path to ground.  I would look to verify proper grounding locations and good clean ground wires.

[EDM620]

9 hours ago, iceman510 said:

The weird behaviors suggest bad ground, as circuits are going through other circuits to find a path to ground.  I would look to verify proper grounding locations and good clean ground wires.

And I've always said the majority of electrical issues are caused by bad grounds. The sheet metal under your ground screws do get rusty on a 40+ year old vehicle.

 

BTW, if you can't resolve, I have a full 620 wiring harness that I no longer require.