Water, Fuel Oil Pressure gauges stopped (1 Viewer)

[Boaf 32]

Fellow LCers,

Been a while since I posted, things have been going well and enjoying the top down Florida weather. Came home from soccer the other nigh and next morning, no Fuel, Water or Oil Pressure gauges. Not sure what happened.

Symptoms: I have Blinkers, radio, lights. It seems to be something with the ignition connector (just a guess based on the diagrams that all 3 go through the ignition for power).

Pulled the Barrel connector and the power, made sure all were clean and re-assembled. Testing shortly. All fuses are in tact.

I did find this on the footwell; not sure if I just picked it up in my shoes, but strange that all 3 gauges stopped and I found this. What is it?

Any thoughts on how to trace the power are appreciated.

Boaf

 

[cruiserkev]

Same thing happened to me. Clean up the areas where your instrument cluster grounds out. I went so far as making a dedicated ground wire for the cluster and it solved the issue.

 

[JVZii]

If it helps, those 3 gauges are all powered through a single wire in the cluster plug. Also a single fuse which I think is different from the blinkers and high beam.

If the fuse is good, check the number 3 wire with a test light and make sure there is power. If there is it's likely a ground problem or the board might be burnt (if you have one not sure if the year your have )

 

[Boaf 32]

If it helps, those 3 gauges are all powered through a single wire in the cluster plug. Also a single fuse which I think is different from the blinkers and high beam.

If the fuse is good, check the number 3 wire with a test light and make sure there is power. If there is it's likely a ground problem or the board might be burnt (if you have one not sure if the year your have )
View attachment 3293331

Thanks JZVii, CruiserKev,

Cleaned the Black and white ground pin and connection. will check the power to #3 today. My LC is 1972 (Mnf 10/71) Will add it to my signature if it is not already there. Will keep you posted.

Boaf

 

[Boaf 32]

Update:
Took a test light to the 12V Ignition port (Blue \ Red wire) and have no juice. Is there some sort of in-line fuse? The wiring on this truck is a Frankenstein (pronounced Frankunsteen) from the PO, I just never updated it.

I will ask the dumb electrical question: If I take power from the battery and bypass it to the Barrel, will that confirm the gauges work?

Thanks for your help.

Boaf

 

[SteadiCruiser]

Update:
Took a test light to the 12V Ignition port (Blue \ Red wire) and have no juice. Is there some sort of in-line fuse? The wiring on this truck is a Frankenstein (pronounced Frankunsteen) from the PO, I just never updated it.

I will ask the dumb electrical question: If I take power from the battery and bypass it to the Barrel, will that confirm the gauges work?

Thanks for your help.

Boaf

I would not connect direct battery to anything instrument cluster related. If you don't already have one I'd immediately go get a multimeter from your local autoparts store to help. I just finished tracking a lot of electrical issues with a newly built harness and reinstall and I could not have done it without one. Particularly the Ohm meter to measure connection integrity without needing electricity present.

 

[Boaf 32]

Thanks StediCruiser,

Yes I have a multimeter. Just need to track the Red-blue for continuity and where it falls apart. @Coolerman , any thoughts on where to start?

I'll pull the wiring diagrams from the Haynes book. I'll do some research, but what is the fuseible link by the battery? It appears it does supply the ignition switch in some way that supplies the blue/red wire (Pin 3) Any guidance is appreciated.

Boaf

 

[liven the life]

@Boaf 32 I also have a 10/71 40 and have had the same issue. Mine had to do with blowing the rear heater fuse. 20A - heater/gauge fuse (3rd from bottom). Also, assuming your gauge cluster is original, the back of it should look like this and not have the cluster plug referenced above?

 

[Boaf 32]

@Boaf 32 I also have a 10/71 40 and have had the same issue. Mine had to do with blowing the rear heater fuse. 20A - heater/gauge fuse (3rd from bottom). Also, assuming your gauge cluster is original, the back of it should look like this and not have the cluster plug referenced above?

View attachment 3294541

Nope, the back of mine is with the Barrel connector. It was "frankensiened" from the PO.

 

[Boaf 32]

Going to pull the ignition key and see if there is something going on back there with regard to the Blue Red wire. It just seem so strange that it said "I'm done". Truck still runs and the alt gauge is working. Aghhh, always something.

Boaf

 

[pb4ugo]

The ammeter gets power from the batt or alt. The other gauges get their power from a fuse in the fuse box. According to previous post in this thread, it gets its power from the heater fuse. Coolermans' website has wiring diagrams.

 

[Boaf 32]

Hello all,

Update: The Oil Pressure and the Fuel Gauge started working again. It's like magic!

The Temp gauge is still not working, but investigating. Thanks and will keep you posted.

Boaf

 

[John McVicker]

Have you checked continuity with your multimeter on the wire from the back of the gauge to the sender on the block? Just to be sure you do not have a break in the wire.

 

[Boaf 32]

Have you checked continuity with your multimeter on the wire from the back of the gauge to the sender on the block? Just to be sure you do not have a break in the wire.

Thanks John, doing that today!!!

Boaf