CJ gauge cluster

[rodeowade]

I was wondering if anyone has replaced the 3 volt inline resistor for their gauge cluster and did you find it fixed any of your gauge problems.

Question 2 ..........If this did help where does one find this resistor....


FYI.......I am in process of restoring a 79 CJ5.....the gauges dont work and would like return all of the operations back to factory or as close as I can....................................................................ThanX

 

[jay79cj7]

I've been all through my 79 CJ gauges, but I don't know what resistor you are talking about. Any details on this?

 

[rodeowade]

I have not seen this 3 volt resistor, I use a chilton's book for reference and thats were I read about the in line 3 volt resistor located from the book it says "On or near or just under the gauge cluster" goes on to say most gauge clusters are 9volt and that thats why you need it to drop it from 12 volt to 9 volt ....I guess.....

 

[jay79cj7]

Are you sure you are looking at the right model year? There is no such resistor on mine and all my gauges work, unless they are built into the guages themselves. Where in Chiltons do you see this? I have one, I'll pull it out.

 

[rodeowade]

Well in chiltons book chapter 6-19 it goes into the removal and installation of the instrument cluster....

1st paragraph ......... "on these vehicals the instrument cluster is actually the speed/gauge assembly that is located in the center of the inst. panel ...most vehicals covered by this manual are equipped with 9 volt gauges which require the use of a in-line 3 volt resistor (mounted under the dash on or near the cluster) the resistor or resistors depending on make and model should be suspect in the event of improper gauge operation".....


now I have a 79 CJ5 so maybe there is not one ...all I know is that only the speedo is working ......Im just trying to fix all the after-market crap the previous owner tried to jimmy-rig it with...........

 

[jay79cj7]

I can't find my Chiltons now. I can tell you that I have no inline resistor, and all of my gauges work appropriately. That comment must be for earlier years. Yours should be the same. What is wrong with your gauges?

 

[rodeowade]

well when I got this one I was told the fuel gauge did not work because of the sending unit but before i drop the fuel tank to do that I wanted to check other souiltions....thats when I noticed that the temp does not work it is just stuck on the last temp before it stoped working and the oil presure is also stuck on the last reading before they stoped......I read that statement in the book and was thinking maybe just one time I might have got a easy fix ...i am just going to have to go through each gauge and trace them out...

 

[jay79cj7]

The fuel, temp, and oil pressure gauges work by having one terminal hot and grounding the circuit through the sending unit. The sending unit varies in resistance with pressure, temp, etc, which varies the current going through the circuit, which makes the gauge show different values. One extreme of the gauge equates to max sender resistance, the other to min. To diagnose any of them, make sure you have a live 12v source hooked to the right terminal and then ground the other. If the gauge works, the needle should move. (I have heard you can damage the gauges by having them grounded directly like this, so I recommend just tapping the ground to the terminal just long enough to see the needle jump.) Also, you can check the sender by using a multimeter to measure the continuity between the sender and ground. There should be some resistance. If you have an open circuit, then your sender or sender wire is probably bad.
CJ gas tank sending units go bad all the time I hear. I just had to do mine last year. The fact that all of your gauges don't work probably means you have a blown fuse or a bad 12V source going to the cluster.

 

[rodeowade]

Right on .....I get in there and hook my multi meter to see where im at ....one thing at a time ....i'll get there.....I am in the process of having to change my rear-crossmember right now thats a headache...but since thats all apart at the moment I can change the fuel sending unit anlong with the cross-member. thanks I'll post anything new and again thanks for your help.

 

[redneckgroundhog]

Here ya go. This pruty much has it all. Good luck!
That's 'bout it!

http://www.4x4wire.com/jeep/tech/electrical/gauges/

 

[ndnatty]

The link redneck gave you should get you fixed up. I have a 79 CJ-7 and the original fuel gauges are a bear to keep running correctly if you don't have a good ground to the system. It easily burns out leaving both the fuel and temp guages down. I have an aftermarket replacement on it now that uses an internal resister to regulate the voltage to the fuel gauge. Now it seems to work fine and has been working for some time now. Good luck with your project!

 

[jehartma]

Don't know if this will help, but I think the resistor is the metal "L" that connects the fuel and temp guages. Good luck with the gauge diagnostics. Went through the same thing about a year ago....ended up buying a new fuel guage and fixed it right up. If you decide to drop your fuel tank and install a new sender, test out the float to make sure it does not have a leak. Mine did, and I had to go through the process four times before I figured out the float was a POS. Ended up using the old float with the new sender. Good luck!