CJ-7 electrical problems?

[cdlongjr]

I just got my 1983 CJ7 home last night. It's been setting in a garage since it was repaintd 3 years ago. It hasn't been started. When I got it, the fuel & water temp gauges didn't work. They were all the way down to the left. After a few miles of driving, I saw both gauges were pegged to the right. I stopped & the gas tank held $17.00, I pulled the pressure release lever up on the radiator cap & nothing came out. I removed the cap & the level was good. Any ideas?
Thanks,

 

[CJ]

That's one big gas tank you have there! It took $17 and was full! :laugh:

OK, enough idle chat.

Sounds like a short in the gauge cluster. The individual gauges work by grounding (resistance). If the sending unit shows zero resistance(full short to ground), the gauge swings all the way to the right (full or hot position).

Since the gauges have completely separate sending units, about the only place that they could be picking up a short to ground is around the cluster. The wires entering the cluster are separate so they would both have to be shorted to ground to affect both gauges.

That is where I would start...

 

[mylittlecj5]

according to this diagram there is very few areas that affect both guages.
I hilighted the parts you should check into. Hopefully it works..

 

[CJ]

Thats great! You have a diagram. I only have a 72 diagram.

Did you scan that? I tried zooming in but it gets a little hard to read. Can you save it as a larger attachment?

 

[mylittlecj5]

actually I get all my diagrams from autozone.com (repair section).

I'll look it up again and post the link

 

[mylittlecj5]

 

[CJ]

That is great! Even my old eyes can read that! Thanks!

 

[BrockGrimes]

Gauge stuff in this link:
https://jeep-cj.com/community/threads/useful-info-thought-id-share.665/

 

[cdlongjr]

Your old eyes huh? How about mine, after all I am "The ole fart". Now would ya'll please ell me what I'm looking for & possibly how to get the panel out? I tried gettin' behind the panel. Not in this life time.
Thanks

 

[CJ]

I'm going to have to let a later model CJ owner chime in here... My early CJ has a completely different cluster then yours...

 

[dave pam]

As BrockGrimes mentioned, Autozone is very help full, they will even test stuff for free and also test codes for free, I use them when I can.

Dave

 

[2lostspace]

My 82 CJ7 had the same problem at some point and time and the PO put aftermarket fuel/temp gauges that work fairly well. I would like to know what you came up with maybe give me some kinda idea on what to look for in repairing my original set.

 

[BrockGrimes]

Gauge stuff in this link:
http://www.jeep-cj.com/forums/f49/useful-info-thought-id-share-665/

See above gauge thread

 

[cdlongjr]

Upon trying to remove the nut on the lower left stud that holds the speedo in, the stud came off. There' a white wire on the stud. Do I have a problem?

 

[CJ]

Sounds like someone needed a spot to hook up a ground. Just put it back to another ground spot when you reassemble the components.

 

[mylittlecj5]

JB Weld the stud back on.

 

[abnergladys]

My 83 CJ7 has had the same problem but it is intermittant. Now today I used the tests posted by By Brockgrimes.http://www.jeep-cj.com/forums/f49/us...-id-share-665/ . My temp seems to be back on line but Fuel is reading empty. (Went to fill, just to be sure and only took 1 gallon). About to remount the 5 gallon can and bag it! HELP!Now a new twist, the battery is going dead after sitting a few days.

 

[gert]

Have you guys checked to see if your getting good grounds? Rust will stop your electrical connection in a hurry and vibration would make it intermittent. I work on aircraft and our Test Winne's are fanatical about good grounds

 

[abnergladys]

Here is a new twist. got some quality time with a buddy that gets electricity, (Technically) Traced my my main problem to a defective turn signal switch. it was new from Auto Zone. Found it was feeding back through system and had an open ground! I hate electricity! How this could affect the gauges I'll never know.

 

[LongHorn]

Here is a new twist. got some quality time with a buddy that gets electricity, (Technically) Traced my my main problem to a defective turn signal switch. it was new from Auto Zone. Found it was feeding back through system and had an open ground! I hate electricity! How this could affect the gauges I'll never know.

Reminds me of a buddy of mine that's into British sports cars. He had a quote he liked to use. Joseph Lucas, the British electronics famous "Prince of Darkness”

Why do the Brits drink warm beer? Lucas made refrigerators too! I guess they like their beer warm at Jeep too!