Continuing saga of cluster panel

[Finally Mine]

78 fj40 is running fine after carb rebuild, thanks to Pin Heads youtube disassemble/reassemble of the asian carb. Ok, once up and running I notice that the gas guage is not working, so I take out the old sending unit and see it is stuck solid as a rock. Purchased a new one and gas gage is now reading fine. Since I have the cluster panel removed I figured why not clean it up a bit. Found some great threads here and followed along.

I would on occasion put the cluster back in and hook it up to start the 40 as the other parts were being cleaned and painted. Through trial and alot of error I finally figured out why the blinkers and windshield wipers weren't working. The cluster panel had to be reassembled entirely. Like I said trial and error.... So today the cluster panel is all reassembled and ready for installation.

Installed and I started up the fj and all is fine. I look at the guages and the gas guage along with the temp guage are not working. Blinkers and wipers are working fine, but temp and gas guage are not.

Any ideas what may be wrong or what I'm doing? Also the two main screws that hold the cluster to the dash what size are they and where can I get two more? Have misplaced the originals.

Steve

 

[4thHorseman]

I'm a noob here, but I'm going to say what I've seen. =)

90% of all electrical issues with the FJ40 are due to poor grounding.

 

[bj40green]

The Fuel gauge and the Temp gauge are a set. The Fuel gauge "makes" 7Volt for itself and the Temp gauge. Is your Oil gauge working? If not check for Voltage from the Heater fuse.
If your Oil gauge is working than check the printside of the cluster.

It can also be that the 2 screws ( M6 x 16 oval head) are necessary for grounding the cluster.

See also: https://forum.ih8mud.com/40-55-series-tech/544543-clusters-gauges-odo-meters.html

Rudi

 

[Finally Mine]

Rudi, thats where the confusion comes in. When I first removed the cluster panel a few weeks ago in order to start the fj I was only reconnecting the wires back to the pc board, the inner and outer plates were left off for cleaning and painting. All the guages were working fine after I replaced the sending unit in the gas tank. Today when I put the cluster back together and reconnected the wires back to the pc board and started it up thats when I noticed the gas and temp guage not working. Oil and amp guages are both working.

So what was grounding the cluster and having all the guages work when I did not use the two oval head screws? What should I be looking for on the print side of the pc other than the obvious broken or loose connections?

Steve

 

[bj40green]

Power is coming in on #3 and goes to OIL gauge. The OIL gauge is working so you have the 12V at that point.
Below #3 you'll see a tiny track, marked 12V that goes to the left side of the Fuel gauge. Check this track and check for 12V on the left side of the Fuel gauge. The Fuel gauge has 3 connections the one on the right goes back to #4, the Fuel Sender. The top connection is the 7V output for the Temp gauge.
You can't meassure this 7V. You'll meassure alternating 0 and 12V. So the average is 6V at idle and 7V at higher rpm's.
Now, inside the Fuel gauge is a Voltage regulator. If that regulator doesn't work both gauges won't work. Time to get the multi meter out and do some checks.


Rudi

 

[FJfarty]

I'll also be following this thread with interest.. since neither my turn signals, nor my blinkers are working at the moment either.

The turn signals did work for a little while then one day stopped. The wipers wouldn't have worked anyway because they were full of 40 yr old grease, which I cleaned, and now they test good but don't work when I plug them in. The hazards work fine though.

Another funny thing is my dash cluster back light doesn't work either, and one day after it was pouring down outside, the light came on for about a minute then slowly faded away.

 

[bj40green]

cluster problems

My comment in blue,

I'll also be following this thread with interest.. since neither my turn signals, nor my blinkers are working at the moment either.

Hazard and turn is a mixed circuit. The hazards are working all the time and the turns only when the key is "on". The hazard switch is the key here together with the blinker unit. Check the (2 wire) blinker unit first.

The turn signals did work for a little while then one day stopped. The wipers wouldn't have worked anyway because they were full of 40 yr old grease, which I cleaned, and now they test good but don't work when I plug them in. The hazards work fine though.

You said above they don't work at all. Now you say the turn don't work and the hazard work fine.
Most common problem is the hazard switch. When the hazard switch is "off" it re-routes the power to the turn lights.
Clean the hazard switch with WD40 or so.

Another funny thing is my dash cluster back light doesn't work either, and one day after it was pouring down outside, the light came on for about a minute then slowly faded away.

Sounds like a bad or intermittent connection.
Check for Voltage on pin# 10. If there is 12V take out the two light bulbs. You'll see 2 tiny copper contacts on the edge of the socket. Clean those, bend them a tiny bit up to get better pressure to the pc board. Also clean the contact surfaces on the pc board. I use a glass fiber pencil for this.

Rudi

 

[Finally Mine]

FJ Farty, as I said in my first post a great deal of trial and error. When I first assembled the cluster back together the blinkers and wipers didn't work, so I went to the fuse panel. Took the fuse out that was labeled for the blinker and wiper together. Saw that it was still good and reinserted it, and much to my surprise the blinkers and wipers worked. May be something that simple.

Steve

 

[Finally Mine]

Rudi, before going to bed last night I wanted to check the back of the pc board again. What is providing the circuit on the board the darker colored lines or lighter ones? If it is the darker colored lines I noticed a break in the line just above the arch. It was scratched and had white paint on it, probably from when I put the entire cluster together. That is when all my troubles began after putting it together. If that is supplying the curcuit how would you repair something like that? Also on the fuel guage itself the small white wire on the left (oriented looking from the back, F on left/ E on right) looks to have a burn or exposed area. The white coating looks to be removed but the wire is intact.

Thanks for your input.

 

[bj40green]

Hi Steve,

The black lines are the tracks. They are copper and covered with a blue or green transparent laquer.
Have a look at postings #24 and #25 in this thread: https://forum.ih8mud.com/40-55-series-tech/544543-clusters-gauges-odo-meters-2.html
You'll see a cluster with a gap. Does it look like yours?
If tou see a broken track you can scratch off the laquer and solder a piece of wire over it.
You can also make a "bridge" like the one you see in the pics in the thread.

That white stuff around the wire is cotton. It serves as an insulator. As long as the wire is not broken it's okay.

Rudi

 

[Finally Mine]

Yes Rudi, a small gap. I will try soldering the wire over it, but may be easier to bridge as you suggested. If I decide to bridge should I use the same set up as you did in your pic? So it hasn't been a very productive day, in fact one problem after another. How much does tha cluster play in the overall conduction of things throughout the fj. Today, I notice the amps are now draining negative, and I was really careful as to putting the correct wires back in place when I hooked up the amp guage when I installed it back into the dash board. Now the blower, wipers, turn signals, won't work and the emergency flashers work intermittently. Frustration has set in. Need to walk away from the entire deal and refocus. I should have left things alone from the beginning, but I want a reliable working fj40.

Steve

 

[bj40green]

Solder a wire or make a bridge. Doesn't matter. I don't know your soldering skills.

Brake and headlights work? Sounds you have some problems with the fuse box. You've had problems before.
Take them all out, clean the contacts with a fiber glass pencil, thighten the clamps a bit and put new fuses in.
That stuff is over 30 years old.

You can do it.

Rudi

 

[Finally Mine]

Rudi, a quick update on progress. Yes progress! I took your advice and cleaned up the fuse panel. Installed the panel with new fuses and started the 40. Amp and oil guages are working along with blower, wipers/turn signals etc. The only thing that I noted wasn't working was again the fuel and temp guages, along with the panel lights.

Took the cluster panel off and behold the culprit. A broken line that was not obvious in the beginning. It may have happened after all the new fuses were installed. Was clear a day! I will post some picks later but it is the circuit connecting the oil and fuel guages. I am trying a product called a Circuit Writer conductive pen. My soldering skills are not the best and if the pen doesn't work I will make a bridge. Speaking of bridging what size wire should be used?

Thanks again for your advice and encouragement. Taking care of the gremlins one small step at a time.

Steve

 

[bj40green]

Hi Steve,

That wire can be pretty small. AWG16 or 18 or even 20 will do.
The maximum current is less than 600mA (0.6A) and the lenght will be around an inch, so any piece of wire will do.

Rudi