Guages quit working when headlights turned on

Start the '69 Superbee and everything works great. Then, turn the headlights on and the qauges go dead and there are no lights on the
gauges. However, the lights on the clock and the left side of the
speedometer do come on. It used to happen intermittently and when I hit a bump everything would come on. Now only the clock and speedo
work when the lights are turned on. Shut the lights off and the gauges start working again. What's up with this? Is this a bad ground somewhere?

yeah, the bad ground would be my guess.

run a ground wire up to the dash frame, or to the gauge cluster and see if it clears it up.

You say run a ground wire up to the dash frame. I should run a wire from where to where. Keep in mind this thing has a printed circuit.
Thanks

Jim

The dash grounds through the screws that hold the cluster in. Make sure they are clean and tight.

so typically as stumpy said, the screws to the frame grounds the circuit board.

if you look the paths on the circuit board end on screws that are not insulated from the circuit.
those are grounds to the gauge cluster.
the cluster is bolted to the frame, and those are your paths to ground.

IF the "chrome" plastic plating is chipped away, or you painted the dash frame, or if some of the screws are missing, you typically get a bad ground for the circuit board.

you can run a ground directly to the circuit board. just look for one of the screws that dead end a circuit path instead of the insulated ones that don't have any circuit going to it.

I got up under the dash with a light and started tugging and pulling
on the light switch wires and the light bulbs and all the wires
going to the gauges and everything started working. However, I'm sure
it will happen again especially if I hit a bump. Although every time in the past,
it only happened on start up. Does this still sound like a ground?

Jim

Sounds like you need to track down the wire that supplies power to the affected lights and fix the short.

could be a lot of things. grounds are the quickest check.
pulling on stuff is never a good answer.
if anything, it could have shifted the cluster enough to get ground again.

you have to start somewhere. grounds are the best place to start.
especially since there really isn't a common between the headlight circuit and the gauges for power.
while the dash illumination runs through the light switch, power to the gauges goes through the key on.
it isn't likely a power SOURCE is your problem. rather common ground for the 2.

Andrew:

You helped me once before and I'm looking to you once again......

I tried posting this question on the forum but can't get in.

It's a 69 Superbee. Completely restored 9 years ago. All new wiring through out. The problem started about 4 years ago and then corrected itself. This weekend it reappeared!
Now when the headlights are on the green directional indicator lamp on the right side of the dash and the fender mounted turn signal stays on constantly ( doesn't flash).
The green light stays on. The left side works perfectly ( no problem). When the right directional indicator is turned on.........the lights flash as they should with the headlights on or off.
This only happens when the headlight switch is turned on. Any thoughts?

Jim

The guy that just cured the same problem found it was a bad bulb. Check the lights for a bulb that has a different glow then the others. Make sure all the sockets a well grounded also.

OK.....I'll try that. Thanks a bunch.

Jim