Kubota ZD1211 - won't start

texaskubota

Member

Equipment
ZD1211
Feb 28, 2023
40
0
6
Texas
ok.simple test..
according to the wsm wiring, the live +12 from 50 amp fuse goes to both the 20 amp fuse and a 15 amp.
the 15 goes to the 'regulator'.
please confirm it as +12 volt. I think 15 amp fuse are blue ?

this long distance diagnosis is difficult ! but easier than the 2 feet of snow I have to deal with come sunrise tomorrow......
11.6 V on the 20A and 11.6V on the 15A fuse below it. From the signal plug (before the 50A slow blow) all the way to the fuse box.
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,419
4,908
113
Greensville,Ontario,Canada
YES !
Voltage should be seen at the 20 amp fuse, stop solenoid, OPC and the meter panel.
You'll have to 'follow the wire'.. but according to the drawing in the WSM...
starts at the fuse, goes to stop solenoid then goes to BOTH the OPC and the meter panel.
...so 4 places that must have 12 volts on them, live, 24/7..
 

texaskubota

Member

Equipment
ZD1211
Feb 28, 2023
40
0
6
Texas
YES !
Voltage should be seen at the 20 amp fuse, stop solenoid, OPC and the meter panel.
You'll have to 'follow the wire'.. but according to the drawing in the WSM...
starts at the fuse, goes to stop solenoid then goes to BOTH the OPC and the meter panel.
...so 4 places that must have 12 volts on them, live, 24/7..
YES !
Voltage should be seen at the 20 amp fuse, stop solenoid, OPC and the meter panel.
You'll have to 'follow the wire'.. but according to the drawing in the WSM...
starts at the fuse, goes to stop solenoid then goes to BOTH the OPC and the meter panel.
...so 4 places that must have 12 volts on them, live, 24/7..
The R/W on the stop solenoid is showing no signs of life. Ever.

The 20 Amp fuse does have continuity from the 50A slow blow and does get 12V when key engaged.

Ok, so the r/w wire from fuse to stop solenoid seems to be a culprit. BUT....

I showed continuity from the 20 Amp fuse r/w to the stop solenoid r/w. Totally confused with the results there
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,419
4,908
113
Greensville,Ontario,Canada
re:

The 20 Amp fuse does have continuity from the 50A slow blow and does get 12V when key engaged.

That 20 amp fuse should have 12 volts on it without the key 'engaged'. it's live power from the 50 amp which is live from the battery.

You CANNOT do 'continuity' tests on that circuit UNLESS you remove the fuse. If the DMM is set to 'ohms', the circuit has to be 'dead' (unpowered ) NO voltage present

just use set DMM to DC volts, read the 20 amp fuse, then read the R/W wire on the stop solenoid. If it says 12 volts, wire is good, if zero...wire is busted ,open,..
 

texaskubota

Member

Equipment
ZD1211
Feb 28, 2023
40
0
6
Texas
re:

The 20 Amp fuse does have continuity from the 50A slow blow and does get 12V when key engaged.

That 20 amp fuse should have 12 volts on it without the key 'engaged'. it's live power from the 50 amp which is live from the battery.

You CANNOT do 'continuity' tests on that circuit UNLESS you remove the fuse. If the DMM is set to 'ohms', the circuit has to be 'dead' (unpowered ) NO voltage present

just use set DMM to DC volts, read the 20 amp fuse, then read the R/W wire on the stop solenoid. If it says 12 volts, wire is good, if zero...wire is busted ,open,..

Yeah I'm figuratively and literally getting my wires crossed over here

Ok. So.

1. We do NOT have 12V at the 20 Amp Fuse. 0.34v
2. We DO have 12 volts at the slow blow fuse (pin to a good ground)

So, of all things that makes more sense now.

And assuming this diagram isn't pulling any shenanigans, that leaves the 50 Amp to fuse box run as the culprit....or the splice there to the ignition switch.

how is it spliced anyway on these? The harnesses are ofcourse all covered
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,419
4,908
113
Greensville,Ontario,Canada
sorry but you'll have to follow the wire from the 50 amp fuse to see where it goes....
I 'assume' that the splice is made where the wire 'T's off to the ignition switch ?
If the harness is taped ( usual...) you just carefully cut the tape ,peel back a few inches, locate the fat red wire and see what they've done.
Have you any access to the back of the fuse box ? See if there's any corrosion where the fat red goes to the 20 amp fuse ?
the '.34 volts' sounds like a well rotted out wire to me... just enough strands left to pass a small voltage.

I suspect the fuse block area and not a 'tap' in the wiring harness....
 

texaskubota

Member

Equipment
ZD1211
Feb 28, 2023
40
0
6
Texas
sorry but you'll have to follow the wire from the 50 amp fuse to see where it goes....
I 'assume' that the splice is made where the wire 'T's off to the ignition switch ?
If the harness is taped ( usual...) you just carefully cut the tape ,peel back a few inches, locate the fat red wire and see what they've done.
Have you any access to the back of the fuse box ? See if there's any corrosion where the fat red goes to the 20 amp fuse ?
the '.34 volts' sounds like a well rotted out wire to me... just enough strands left to pass a small voltage.

I suspect the fuse block area and not a 'tap' in the wiring harness....

Ok so.

TODAY we had 12v at the 20 Amp AND at the solenoids r/w. (Major head scratcher).

At some point I look at the fuse box and the contacts slot for the 20A. One side seems a bit stretched too wide to make good contact. I grab a flathead and bend it back in. So maybe this was causing the incremental no voltages.

So, try and start? Same issue. I'm getting near my surrender point.

So after the solenoid we have the OPC and meter panel. The (broken) wire for the meter panel now shows 12v. That's a first. So now we're in business.

But the OPC still isn't showing 12v at pin 6. I jiggle, push, and test with a copper wire a handful of times. Nothing. I'm suspecting the plug, but it just seems too solid.

I give in and start untaping the harness. Pain in the butt. I Finally. Finally find the splice and the ultra small pin 6 wire.

It slides right out with a tug. I strip the wire, get 12v on it, and we're cranking away.

Mystery solved.

I owe you a beer for your patience and help, so feel free to message me a payment method
 

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GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,419
4,908
113
Greensville,Ontario,Canada
Whew ! Man I'm happy you got it 'up and running', you sure have patience !!
You really need to clean all the mud and sticks off the HST ! Those cooling fins on it work a LOT better without mud in between them.
Electrical 'gremlins' are a slow process of elimination but you NEED the wiring diagram to 'see' how it's supposed to work. Vibration and corrosion are not nice to wires and stuff.
 

texaskubota

Member

Equipment
ZD1211
Feb 28, 2023
40
0
6
Texas
Whew ! Man I'm happy you got it 'up and running', you sure have patience !!
You really need to clean all the mud and sticks off the HST ! Those cooling fins on it work a LOT better without mud in between them.
Electrical 'gremlins' are a slow process of elimination but you NEED the wiring diagram to 'see' how it's supposed to work. Vibration and corrosion are not nice to wires and stuff.
It will definitely get some air compressor treatment.

When untaping the harness it was quite dirty and had moisture, so I'd be surprised if this isn't a common issue.

Instead of redoing the original splice I'm thinking of just soldering and heat shrinking that tiny wire and running it separately (and protected) to the battery. That wire is such a small gauge, I can see it being a problem in the future. At the very least it will be accessible at the splice without undoing the main harness which has "heavier" less fragile gauge wires
 
Last edited:

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,419
4,908
113
Greensville,Ontario,Canada
Any (every ?) splice can become a problem, you just need a little bit of water to start corroding the wire, make take weeks or months, but it WILL happen.
yes, run a 'full length' wire now while you can, use larger gauge wire if you have it. Hopefully same colour !
if it's 'red with white' tracer, use a solid red wire and wrap thin white stripes at both ends. This way IF you ever have to fix it again, YOU know what the wire's supposed to be for.
The more you do NOW , the less chance you'll ever have to work on it again. It's a 'Murphy' rule.....
 

texaskubota

Member

Equipment
ZD1211
Feb 28, 2023
40
0
6
Texas
Any (every ?) splice can become a problem, you just need a little bit of water to start corroding the wire, make take weeks or months, but it WILL happen.
yes, run a 'full length' wire now while you can, use larger gauge wire if you have it. Hopefully same colour !
if it's 'red with white' tracer, use a solid red wire and wrap thin white stripes at both ends. This way IF you ever have to fix it again, YOU know what the wire's supposed to be for.
The more you do NOW , the less chance you'll ever have to work on it again. It's a 'Murphy' rule.....
Will do! I have wires for days here. 6 awg to 14 and everything after.

What do you suppose that r/w to the meter panel is for? I'd say to power the thing, but the whole panel works normal. Connected (jumped because it broke) or not, it seems to be fine without it. Ofcourse, I haven't actually ran the engine yet, as I'm slow charging the battery after days of start testing (and it needs coolant topped off). Maybe we'll find out after it's first run
 
Last edited:

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,419
4,908
113
Greensville,Ontario,Canada
Based on the 'gauges' wiring diagram in the WSM (5-M17), I'd say the R/W wire is used to sense that the 20 amp fuse is blown and that no power is going to the stop solenoid and the OPC unit.

Power for the meter panel is supplied by pin 15 , R/Y from the 10 amp fuse, ground is pin 7, Blk wire.

Sadly the wiring diagram is incomplete ! Verbally talk about fuel/heat sensors and gauges but NOT shown on the diagram. Student would get a 'goose egg' in my class...
 

texaskubota

Member

Equipment
ZD1211
Feb 28, 2023
40
0
6
Texas
Based on the 'gauges' wiring diagram in the WSM (5-M17), I'd say the R/W wire is used to sense that the 20 amp fuse is blown and that no power is going to the stop solenoid and the OPC unit.

Power for the meter panel is supplied by pin 15 , R/Y from the 10 amp fuse, ground is pin 7, Blk wire.

Sadly the wiring diagram is incomplete ! Verbally talk about fuel/heat sensors and gauges but NOT shown on the diagram. Student would get a 'goose egg' in my class...
Based on the 'gauges' wiring diagram in the WSM (5-M17), I'd say the R/W wire is used to sense that the 20 amp fuse is blown and that no power is going to the stop solenoid and the OPC unit.

Power for the meter panel is supplied by pin 15 , R/Y from the 10 amp fuse, ground is pin 7, Blk wire.

Sadly the wiring diagram is incomplete ! Verbally talk about fuel/heat sensors and gauges but NOT shown on the diagram. Student would get a 'goose egg' in my class...
Yeah I spent way too much time trying to figure out where the OPC was and then had to figure out myself through the comment here and the parts listing I found. (You can't see the wire colors to identify it unless you remove it)

Anyway, I cleaned and put it all back together and now have a direct feed to the battery now for that OPC connection.

Ran great with no issues on the dash. With all the unplugging, fiddling and jumping, especially with those tiny OPC wires, there's always a concern a new problem could be created if something gets pulled too hard or cut.

Again, I greatly appreciate all your help!