Gas Gauge Dead

[SS317]

Ok, I did a search and didn't find an answer.
My gas gauge was/is reading below empty.

Installed new sender from Classic Parts, everything went good, took about 3 minutes.

Gas gauge still shows empty, has not moved.

I followed the wire from the sender, under the seat over to the fuse box where it plugs into where it says "fuel"

Looked behind the gauge and double checked I installed the connector correctly when I took out the gauge cluster. I tried to follow the two wires from the gauge but they get lost in the cluster.

Where are these wires going? Shouldn't one be ground and the other hook to the sender?

[jimmydean]

Have an ohm meter? Put it across the sender, should read between 30 and 0, then put it on the back of the gauge.

I had a short in mine along the drivers floor. Mine goes from under the dash, down the drivers door sill, then up the back and to the tank. If the sender reads and the gauge doesn't, it could be a short. Or the gauge could be dead, but I suspect the wire.

[SS317]

If I were to rewire the whole thing, how would I run the wires?

Sender to back of gas gauge or sender to 12 vdc on fuse box?

I see the diagrahms posted on the site but it's a little fuzzy where the wires go.

Gauge one side to ground I'm assuming and one side to the sender?

I could probably knock out wiring this thing in 30 minutes and make it look great.

[jimmydean]

I honestly don't know what the back of the gauge looks like since I haven't pulled mine yet, but there is a tan or brown colored wire that runs from the sender to the gauge then the sender is grounded to the back of the cab. You could have a bad ground, too.

I am guessing the gauge has the brown wire and a ground wire. I wasn't checking voltage, I was only checking continuity.

[SS317]

I think mine is wired wrong, which wouldn't surprise me.

I'm going to rewire from the sender to the gauge with the brown wire. Right now the sender is going to the fuse block and my gut tells me this isn't right. There is a second wire coming from the back of the gauge and I followed that wire to the bundle that goes into the back of the fuse block. I think that one is the one that is suppose to have power and not straight from the sender.

[SS317]

I fixed it!! Turns out there was no 12 vdc going to the gauge. There were splices after splices all over the place in there. I had to physically trace each of the wires and unwrap all of the electrical tape on the bundle. Different color wires spliced together, it was a mess. I cut it all out and made it pretty.
Great learning experience. Now I can answer questions about fuel gauges.

[Captainfab]

Glad to hear you got it figured out. Electrical issues can be a pain.

Originally Posted by SS317

I fixed it!! Turns out there was no 12 vdc going to the gauge. There were splices after splices all over the place in there. I had to physically trace each of the wires and unwrap all of the electrical tape on the bundle. Different color wires spliced together, it was a mess. I cut it all out and made it pretty.
Great learning experience. Now I can answer questions about fuel gauges.

[steve'62]

i have power but the gauge pegs.....any ideas?

[SS317]

Check grounds. If it's pegging it means the gauge is getting the full 12 vdc. As the gas level in the tank goes down, the sender increases resistance to the 12 v, sending a lower voltage to the gauge. Check and see if the sender is stuck or if there's something goign on there.
Does this help?

[protrash64]

I see you have it figured out, but for info; all the pink wires tying into the gauges are the 12v in and they ground out on the block or on the tank, for instance.

[steve'62]

ss317, thanks I'm gonna check it out, and yes makes sense, other question is the correct plug on the fuse box, its seems alot of the words have worn off!

[mater63]

steve check your new sending unit ohm rating mine did the same thing after i changed my sending unit wrong ohm rating & it fried my gauge

[steve'62]

hmmmm, thanks mater...hope my gauge isnt toasted