M7030 Electrical Problem

[bsekf]

I have found a small parasitic drain (short), so I looked at the fuse block and found a zip tie holding it together. Eureka moment! I'll bet that's where my drain (short) is. Off to the Kubota dealer to see if I can look at a parts picture and schematic to see what it is supposed to look like and see if I can order a new one. Then I look for a electrical mechanic! Hate to tear into it since the tractor works, just no idiot lights. Alternator, glow plugs, temp. gauge, fuel gauge and switch work. I can always just disconnect the battery terminal. Anybody been down this road?

Bill

 

[Dave_eng]

Bill

There is a serial number break in which fuse box fits your tractor so be certain to bring the serial number with you.

The parts illustration is not very clear as you will see below:



I quickly looked through the WSM and did not see any useful info on the fuse box.

Not to discourage you but I doubt the broken fuse box is causing your small battery drain. Fuse box issues cause blown fuses or electrical fires because of serious shorts to ground.

Dave

 

[bsekf]

Fuse panel is available for $125. Since there is no guarantee that's where the short is.....I am going to fool with it. With my Harbor Freight multi meter set at 200ma, it reads 1.5. The simple thing may be a battery disconnect. The oil pressure idiot light would be nice though.
Parts guy said the zip tie might be because the ears are broken.

Thank you

 

[GeoHorn]

Does your low-fuel warning lamp work? It also doubles as a charging-circuit warning lamp.
If someone got tired of seeing a low-fuel warning because of a failed low-fuel-sensor…..

That’s just one possibility. The most likely drain is a failed alternator diode or mouse-eaten wiring…. not a zip-tied fuse box.

 

[Dave_eng]

There is a neat trick which sometimes works when trying to find a small parasitic battery draw when the tractor is off.

Some styles of fuses have 2 tiny metal pieces on the top of the fuse. One connected to each fuse terminal.

If you have a multi meter set to read DC millivolts, touch each meter probe to the tiny metal spot on the top of the fuse.

If any current is passing through the fuse there will be a small voltage drop from one side of the fuse to the other.



This test is best done on a comparative basis. By that I mean check each fuse and if one reads much differently than the others, that fuse's circuit needs a deeper investigation.

Dave

 

[Mark_BX25D]

I think that 'test' is probably urban legend. That voltage drop is so small you'd need a very sensitive meter to read it. As in, laboratory sensitive.


A better way is to make a couple of pigtails with .250 male connectors on one end. Pull the fuse and plug the male ends into the fuse socket. Now you can measure the actual current going through that fuse.

 

[GeoHorn]

There certainly IS a “small voltage drop” thru any fuse due to the resistance in the fuse’ own conductor. (and without a specified voltage-loss to compare to a control conduit…the ”test” is definitely not valid.)
The test-points in a fuse are for the purpose of testing for continuity… not for voltage loss.

However, if a BLOWN fuse were inserted into the holder…. and a current were detected across those test points…. that would indicate an active circuit. (It would be just as easy to pull the fuse and simply place the probes directly onto the female fuse-sockets to accomplish the same test.)