Hi,
I have a '67 SS. Only had it a few months & been trying to check things out before spring gets here. Have some problems with my in dash gauges. Fuel gauge stays just under half with an empty tank, brake warning light is on but brakes seem to work just fine, with key in on position I believe gen., oil pres., & temp. idiot lights should be on but they are not. Was thinking about pulling instrument cluster but not sure how big a job that would be. Any help would be appreciated.

 

Welcome, tmhill, congrats on the '67 SS.
You may have to pull the cluster
Use this sheet for troubleshooting the warning lights.
On gas gauge, ensure ground wire at tank, it's on the fuel tank strap, is making good connection and check the connector in trunk by the latch.
Tan wire goes to the gauge, and you might get a 0-100 ohm potentiometer and connect one outside leg to ground, the middle leg to the tan wire and rotate the pot to see if gauge works.
You could use a 0-500, 0-1000 ohm pot also.

 

Thanks for the wiring diagram. Yesterday I disconnected the tan wire, from the sender in the trunk, and the gauge went to full. When I grounded that wire it went to empty so I think the problem is with the sender. I will check the ground wire & will lower the tank & check wire at the sender. Is there a procedure for pulling the cluster if I have to do that?

 

Disconnect all behind it, unscrew screws seen, and unscrew top ground strap above bright light indicator.
You could do an ohmmeter check of the sending unit to ground for checking continuity, 0-90 ohms should be read.
If no power on fuse panel, problem is before fuse panel.
Might look at horn relay buss bar and remove wires connected to it and wire brush the snout out of it.

 

That's how it's supposed to react. Your wiring from back to front, at the gas gauge, and the gauge itself is fine then. The problem is with the sending unit, or it's not grounded well. I'm putting bets on it being a bad sending unit.

 

Thanks again for your help. It appears that I got the fuel gauge working. As I was unscrewing the ground wire from the frame, the wire slipped right out of the connector. It wasn't crimped at all. Put a new connector on & grounded it to the frame, put some gas in & gauge needle moved up. So, I guess it was the ground. But, when I turn the ignition key to off the gauge needle does not go to empty. I believe it should.

 

Very good in troubleshooting.
Normal with power off. Gauge needle usually stays at last position when powered, unless its off to the side, then gravity takes over and needle may fall to the side.

If gauge works now, don't keep fixing it until it breaks.