Newbe to jeeps

[Tom9961]

Looking at a 1979 jeep cherokee.

Where is the fuse box located? Is there a fuse for the fuel gauge?

[PossumJr]

Fuse block is under the dash, on the firewall above the parking brake pedal. If you haven't already, download the 1979 service manual from oljeep.com as it will likely become a good friend if you buy it. No fuse for the fuel gauge unfortunately, do none of the gauges work or is it just the fuel gauge that is dead? There are a few things that can be at fault.

[Tom9961]

Thanks PossumJr,

Don't know about the other gauges. I stopped for a quick driveway and did't have time to really check it out. I did meet the owner and he told me about the fuel gauge. Hope to get back sometime this week and give it a complete going ove

[PossumJr]

If you get around to looking at it more, what to look for with the gauges is if the temp, fuel, and oil pressure (unless a PO removed the sender to install a mechanical gauge like my J10) all work. All the ancillary gauges run off 5 volts supplied from a regulator in the temp gauge so if none work that is a possible thing to keep in mind, if only the fuel gauge is not functional then it will likely be either a bad sender or bad connection somewhere in the circuit (bad ground is a common thing). Ammeter is not relevant but if that is dead it's worth asking if the owner has done anything with it such as bypassing it.

[will e]

The fuel, temp and oil gauge will all not work if there is an issue with a fuse or the voltage regulator for the dash.

If it's just the fuel it is probably either a broken wire or a bad sender.

Welcome to the group!

[deckroid]

I have had my 84 Grand Wagoneer since Oct 2016 and the fuel gauge has never worked. I believe it to the the sending unit, but I just keep track of miles and every 150 to 175, I stop and refuel. Took it on a road trip of 800 miles round trip and I never ran her dry stopping every 2 hours or so.

[letank]

79 has the access plate under the rear bench and under the carpeting... it will be a good time to change the rotten fuel line and derust the ground reference wire at the sender, cut and install a new spade terminal... which of course is grounded by the undercarriage near the rear bumper... take a peek and you will see those rusted screwed ground wire... or even dangling...

[tgreese]

There is a procedure in the TSM that you can follow to test the gauges. Jeep specifies a special tool, but it's simply a box with a switch and a few fixed resistors. Get some clip leads and resistors of the spec'd value and you can eliminate the special tool.