68 850 Spider Dash Lights

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Garage Time TV
Hey everyone! Wanted to reach out with a question.

1968 850 Spider.

I’m having some wiring trouble. I cannot get my dash lights, blinkers, or headlight indicator to come on. The hazards work, as the flashing indicator on the dash comes on as well as the clicking of the relay. Headlights work, cabin lights work as well as the flashing taillights, but no flashing front blinkers while the hazards are on. While trying to use the turn signals I get nothing. No lights. No sound. I put my multi meter to the column. 0.02v at the blinker switch. I also get 0.02v at each gauge light. I went to the dash light switch and also get 0.02 volts.

Any ideas of suggestions are appreciated. I have already cleaned all grounds as I know that’s a common go to solution. Also checked fuses and all good.
 
Often the grounds are interlinked at each component meaning there is a ground wire into the gauge and a ground wire that leaves and goes on to the next gauge or component. These two wires are crimped together in one spade connector.

I have had the connection within this connector be bad so that none of the components prior to the connector have a ground.

I discovered this because one element in the string did work so I tested at each connection to verify the failure point.

The lesson being that a connection that looks perfectly good may in fact have a hidden failure. So test all along the path not just the end point.
 
Thank you so much! Would a continuity test work to find the bad spot? Start at the first and move long the gauges? Maybe start at each end and come together until the beeping doesn't happen?

Also, I have A-J on my fuse box, but the diagrams stop at H. Does anyone know why this is?
 
Probably so. I have dual orange wires on one spade connector that blow my fuse. As soon as it is unplugged the fuse is fine. Any way to find the short in a practical way without ripping everything apart?
 
Yes, follow the wiring diagram. One of the orange wires goes to the switch cluster (hazard, lights). The other goes to the rear of the car. Do you have a wiring diagram for the coupe?
 
I have the complete book from Midwest-Bayless. Has every type of 850 wiring diagram, but I have been deep in the Spider diagram (since that is what I have) and its various versions. I will look at the coupe one. This may be my whole problem to begin with. I will test there too and i very well could just have an exposed connection touching the body somewhere.
 
Thank you so much! Would a continuity test work to find the bad spot? Start at the first and move long the gauges? Maybe start at each end and come together until the beeping doesn't happen?

Also, I have A-J on my fuse box, but the diagrams stop at H. Does anyone know why this is?

You can do that which will allow you to go from connector to connector or use a regular tester. With a regular tester you turn on the lights, attach the end of the tester to a good ground and then touch the first ground point, working along until you find where it won’t light up (meaning that one has a bad connection to the electricity from the bulb.
 
For a moment I thought you had a coup sorry when you're comparing wiring diagrams make sure you're comparing the correct one for your year and that it's a USA model not of European model they are different as I found my chagrin
 
I colorized a version if you would find it useful.
 

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I’m having some wiring trouble. I cannot get my dash lights, blinkers, or headlight indicator to come on.

For the dash lights & headlight indicator light issue, have you tried turning up the rheostat for these lights to full intensity? It's the knob in the center of the dash, next to the cig lighter (below the ashtray).

The hazards work, as the flashing indicator on the dash comes on as well as the clicking of the relay. Headlights work, cabin lights work as well as the flashing taillights, but no flashing front blinkers while the hazards are on. While trying to use the turn signals I get nothing. No lights. No sound.

This can happen when the front turn-signal lamps get corrosion between the socket & the sides of the light bulb base, or corrosion on the bulb's contact points. Can also happen if the filament for the turn-signal part of the bulb is burned out.

With the exterior lights turned on, are the front indicators under the bumper (parking lights) also on (solid, not flashing)? If so, your problem is likely a burned-out filament or corrosion on that particular contact point of the bulb base.
 
Yes the rheostat is all the way up. I also played with it at different positions with no luck. My dash lights have worked in the past, so I am sure it is something I am missing and right in front of my face.

I had actually just taken off the front bumper along with the turn signals attached. I cleaned the terminals as well as bench tested the bulbs as good. They were working before, just not now. I am about to work this afternoon on getting a resolution. I will come back with a solution! (I hope lol)
 
SOLVED!

I did a continuity test through all the solid white wires which power the gauge lights. I also did it for the grounds. All came out good. I pulled the dash completely out to go wire by wire making sure everything was in the correct place. Thanks a million to the above color coded version! It was a big help to double check my black and white version. Sometimes it is hard to tell where wires go at large intersections.

As I was checking wire by wire, my hazard flasher light had a different wire on it, clearly from a previous owner. I referenced the diagram and saw the orange wire needed to be in its place. Low and behold the factory orange wire was tacked onto the back of a gauge, tripping the fuse. I corrected this and no more problem.

My dash lights work (with the dimmer too!), my blinker signal on the dash works as well as "headlights are on" indicator. I get nighttime running lights at each corner and my front signal lights also work. (my passenger front is burned out so I am replacing it)

Thank you so so much to everyone who had input on my issue. Every instrument in the car works now, down to the engine compartment lights and cigarette lighter. Y'all are the best! Thank you again!

P.S. My reverse light works too! Never knew if it did or not. Great day of progress!
 
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