Cyriac

Hello,

My 4.0 is giving me electrical troubles.

The gauge cluster has always been functioning randomly...

On 1989 the speedo is mechanical and that has always worked fine.

The Fuel gauge has always worked sporadically, giving me an accurate reading rarely. So have the dummy lights, the only one that ever worked was the oil light that shined occasionally. After research I concluded that both sensors for the fuel and oil were bad or old.

Recently the oil light has always been off and the fuel gauge spun around like a clock and locked itself at around 4 o'clock.

So I decided to upgrade to a gauge cluster with the tachymeter (rev counter) and all other needles (new style). I got one and it fit right in but the nothing works. No revs, no battery and fuel. No oil or temp because I haven't replaced the sensors yet.
The temperature gauge is the only one that "slightly moves" all other needles are fixed.

I have read on this subject and many told this could be a ground issue. So I redid all my ground cables and battery cables except starter positive. here are pictures of my current ground setup:

This is the lower dash ground cable that I relocated in the kick panel. I drilled, scraped and screwed the connector here.


This is my battery (that came with the Jeep). As you can see I replaced everything that connected to it and even added a ground to the radiator mount. The only original cable left is the starter positive.


The stock flimsy braided ground was replaced by a new, wider copper braid. All surfaces and the braid ends have been scraped and cleaned.


Here I poorly show how I connected my main ground to the block at the dipstick support. The second black cable goes to the starter negative and the braid was leftover so I decided to fasten in to the cylinder head. Why not?
All ends are between the dipstick and block. I cleaned the surface but wasn't quite able to scrape it off. The surface looked cleaned after some degreaser spray.


A final shot of part of the wiring harness. Unplugged connectors must be for the optional modules that I don't have (Base model) or emissions equipment that have been removed?


A final note, when I replaced the engine bay grounds engine operation was smoothed a bit but that might have a been a psychological effect of my money spending!

None of the ground modifications have affected the gauges in the slightest.

I have no proof that the cluster is bad, I assume it was in normal functioning order when dismantled. It sparked to life for a brief second (all needles moved) once while I was at the wheel but never since. I have scraped and cleaned the gauge cluster connectors.

The battery is a discount model for regular cars so amperage might not be ideal. I suppose it has nothing to do with it?

I'm really stumped and would be glad to hear any additional tips!

Cyriac

Bump... Can someone please review my current setup?

Cyriac

Bump 2! Someone has to have an idea!

cruiser54

I read it. Sounds like you've done one hell of a job working on this issue.

I suspect something in the gauge cluster harness. Can you wiggle the under dash harness while someone observes the gauges with the key on?

And, I'll bet the fact that it seems to run better is NOT your imagination......I've experienced that numerous times after the ground refreshing/adding.

DFlintstone

I'm pretty sure you need to change both the oil pressure and temp senders when changing from a light to a gauge. Btw, I need a temp sender for a light, (top rear on the head). Don't can it!

Cyriac

Thanks Cruiser, You were the person I was hoping would answer!

I'll have to test the wiggling technique. I did try it lightly to no avail.. I'll try again.

As a side note I have had trouble with the fuse panel. My glovebox and dome lights, turn indicators and hazards will function randomly if I press and wiggle on random areas of the panel (discovered this will checking fuses). It seems like the panel is not secured in place, could the loose screws affect it that much???

Could this be a possible cause? Should I remove the fuse panel and check the connection behind it or should I tighten it down properly? Do the gauges even go through this fuse panel???

I knew this but wanted to check the other needles before changing sensors.


Thanks for your responses guys, I really appreciate it. I hope we get to the bottom of this!

cruiser54

Manual transmission? Has a clutch cylinder leaked on to the fuse block?

Loose fuseboxes are not good. Get that straightened up first.

freegdr

Get correct sender/sensors . Check for power in and out of fuse with test light/meter with key on. Also on my 89 there more than 1 ground wire attached to my block by dipstick tube ? And morning Major.

cruiser54

Mornin General.

Yes. At least 3 wires at the dipstick tube stud on all years.

Metal Head

I had this issue and realized all the little metal clamps inside the fuse box that hold the fuses in place were all rotten and weren't getting a connection, it is also possible the gauge cluster is just bad.

Cyriac

Turns out it was a wonky fuse that held only with 3 out of 4 clamps inside the block (don't know why!)

I wiggled it until secured and magically everything started working, everything!
Maybe all my efforts paid? The fuse is really the only thing that made a difference.

So it's all good now! :-)