Green Tractor Talk banner

1 - 18 of 18 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter #1
Hi I am stuck on this tractor problem. I replaced the starter switch because the key was rusted in it. Then changed the solenoid and still wont start. Battery very good, new start switch and solenoid, checked all safety switches and wires, cannot seem to find a fusible link that people tell me to check. Can anyone help me I am not finding the problem not getting 12v to the start switch??
 

·
Premium Member
Joined
·
1,688 Posts
Try this

wiring-diagram-john-deere-lt155-15-amp-11.jpg
 

·
Registered
Joined
·
536 Posts
RustB, Not sure, but the fusible link may be difficult to recognize. They're usually just a "fat" area in the wire with the actual link inside the "fat" area. If you have 12v at the starter motor and 0v at the wire going into ignition switch, the link is blown. Bob
 

·
Registered
Joined
·
10 Posts
Discussion Starter #4
Fusible link

RustB, Not sure, but the fusible link may be difficult to recognize. They're usually just a "fat" area in the wire with the actual link inside the "fat" area. If you have 12v at the starter motor and 0v at the wire going into ignition switch, the link is blown. Bob
Hi Bob, I found the fusible link and it was blown. I replaced it with a diode from my parts bin and tested ok. But still don’t have 12v at the switch? I also pulled 5he 4 relays and took them apart and cleaned them and bench tested them all good. I wonder if it is the Stator is bad? The battery voltage goes through the fusible link then up through the engine shroud as a green, black (red)12v and 2 white wires one goes to the coil. I have taken out all safety switches out cleaned with contact cleaner as the relays. I tested all wires, grounds and hot leads still nothing.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #5
Fusible link

RustB, Not sure, but the fusible link may be difficult to recognize. They're usually just a "fat" area in the wire with the actual link inside the "fat" area. If you have 12v at the starter motor and 0v at the wire going into ignition switch, the link is blown. Bob
Here it is
 

Attachments

·
Premium Member
Joined
·
1,688 Posts
Why would you put a diode in place of the fusible link?

If the diode is in backwards, you won't get voltage to the switch, and if it's in backwards, the breakdown voltage of the diode has to be greater than the battery voltage, or it'll fry it.

The wiring diagram I posted shows the battery going through the fusible link to the ignition (key) switch. It should attach to terminal 'B' at the switch. If it were me, I'd remove the diode and use a piece of wire to jump the fusible link, then check if you have 12 volts at terminal B. That'll tell you if the wire going from the starter solenoid to the switch is good (minus the fusible link). If you measure 12V, I'd cut the fusible link out and replace it with an inline fuse holder. I don't know what the equivalent amp rating of the fusible link is, so I'd start with a 10 amp fuse in the fuse holder. I think a 20 amp fuse is the most you'd want to try if the 10A fuse blows.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #7
Fusible link

I put the diode in correct and I replaced it because that’s what was in there not a piece of wire. For some reason I cannot get 12 v at the switch red wire before the fuse link was replaced or not. I tested all the wires in the start circuit and come up with nothing. I used an ohmmeter with continuity point to point on wires. I don’t get it?
 

·
Registered
Joined
·
536 Posts
RustB, If you found a diode instead of a fuse link and still don't have power, I'm thinking you replaced the "V2" diode...just above the stator in the diagram. Fusible link is still there someplace and prolly still blown! I'd follow Kylew's suggestion and mount a fuse holder. Rewire from starter solenoid to fuse holder and other side of fuse holder to ignition switch. Connect red wire from stator to fuse holder...ignition switch side I believe.

Also, check voltage at starter solenoid, you could (???) have a bad/broken battery cable. Bob
 

·
Registered
Joined
·
10 Posts
Discussion Starter #9
Fusible link

I already stated that I tested the whole harness including the battery wires and there all good. This was a point to point test.
 

·
Registered
Joined
·
536 Posts
Follow red wire from switch (210 on diagram) back to where it joins with the other red wire (220 on diagram) and check for voltage to ground. There should be a third wire, or something there at that connection. Find the other end of that "something"...prolly at solenoid... and check for voltage to ground.

Corrosion on connections can sometimes show continuity, but will not carry voltage/amps. Bob
 

·
Registered
Joined
·
536 Posts
As a side note, if the fusible link was replaced by a diode, either you won't have power to the ignition switch or your battery won't charge! Bob
 

·
Registered
Joined
·
10 Posts
Discussion Starter #13
Red Wire

Ok looks like the diode shown is correct it is V2 and it was blown when I felt the red wire which turns to a black wire then I traced it to the stator so now it’s either I have not found the fusible link or the stator is bad since it connects to the red 12v line?
 

·
Registered
Joined
·
536 Posts
Rust, Some re-wiring has been done, judging by your photo of the diode that you replaced. You should have 2 wires coming out of your stator, one green, one possibly yellow. Yellow (??) should splice into another yellow with one end going to the diode and the other end going to a plug. The diode should have a black on the opposite end going to another plug. Follow this wire...the way the arrow shows on the diode...and this should go to a plug with a red wire going into the plug. Follow this wire back to the next connection...THIS should be one end of the fusible link! The other end of the link will go to your starter solenoid where you + battery terminal connects.

Plan B: START at solenoid terminal with battery terminal on it. There should be a smaller red wire on there also. THIS is one end of the fusible link. Follow red wire to next junction/plug. Disconnect and check for voltage...I'm thinking you're going to find "0" volts!

One more point of confusion on my part. On the V2 diode, verify the arrow on the diode is "pointing" towards the wire on the solenoid, or away from the stator.

Check things out and get back, Bob
 

·
Registered
Joined
·
10 Posts
Discussion Starter #15
PlanB

Ok your Plan B: START at solenoid terminal with battery terminal on it. There should be a smaller red wire on there also. THIS is one end of the fusible link. Follow red wire to next junction/plug. Disconnect and check for voltage...I'm thinking you're going to find "0" volts!

I checked this wire that goes from the solenoid and it’s think red wire it also has a smaller red wire with a ring terminal and the other end goes to a 4 wire connection that unplugs. But in the plug the red wire changes to a black wire then goes to the diode wire that burnt up. It was in a piece of heat shrink and it connected to a black and 2 white wires that go to the stator.
That’s the black wire I felt and it had a bump and I cut it open and found that burnt diode. I think that schematic I’d for newer models because it also shows a voltage regulator but the engine cover has a plastic cap that pops off and was intended for the regulator.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #16
Plan B

Ok your Plan B: START at solenoid terminal with battery terminal on it. There should be a smaller red wire on there also. THIS is one end of the fusible link. Follow red wire to next junction/plug. Disconnect and check for voltage...I'm thinking you're going to find "0" volts!

I checked this wire that goes from the solenoid and it’s think red wire it also has a smaller red wire with a ring terminal and the other end goes to a 4 wire connection that unplugs. But in the plug the red wire changes to a black wire then goes to the diode wire that burnt up. It was in a piece of heat shrink and it connected to a black and 2 white wires that go to the stator.
That’s the black wire I felt and it had a bump and I cut it open and found that burnt diode. I think that schematic I’d for newer models because it also shows a voltage regulator but the engine cover has a plastic cap that pops off and was intended for the regulator.
 

·
Registered
Joined
·
536 Posts
Rust, What you're describing sounds like we are looking at the wrong schematic, so thus is going to make things more difficult to troubleshoot! With me being in TN and you being someplace else, all I can do is ask more questions.

4 wire plug: What color are the wires going into and out of the plug from the solenoid (2 reds, a purple, and a black)?

You said tractor will not crank. With key in "Start", do you have 12v to purple wire or start solenoid?

If you remove (should be red) wire from "B" terminal on ignition switch, do you have 12v on that wire? If no voltage there, follow wire back to next connection and check for voltage. This should eventually end up at battery connection on solenoid.

Post your tractor serial number. Hopefully someone following this thread may have the correct schematic. Bob
 

·
Registered
Joined
·
10 Posts
Discussion Starter #18
Lt133

Well the John Deere is fixed. I used my test light and rechecked all the 12v starter wires and found a broken red wire and a burnt blue wire which fed the headlights. Once I replaced then it fired up. Also I left the diode in as the fusible link and it works fine. Thank you all for your input and the schematic is from a newer tractor not the one my son has. He is happy now he can mow.
 
1 - 18 of 18 Posts
Top