John Deere 310D electrical problems, please help!

[KyHeadhunter]

Well, after about 5 or 6 hours of studying the wiring schematic for the hoe, I figured out a good test sequence and followed through with it. I figured out which wire in the main harness plug between the cab harness and engine harness and tested for signal to crank there. Had signal coming from the cab side, but no continuity between the engine side of the plug and the K1 starter relay. With the sheet metal I had already removed, I could see all but about 6" in the harness and everything looked good, but the tests don't lie. So I pulled the hood and air cleaner assembly out of the way and sure enough I found another chewed spot in the harness. Three wires were chewed in half in this spot and I was able to make proper repairs without having to pull the harness loose. I took a couple more pics and will post them up in a little while after I get all the sheet metal put back on. It will be real nice to finally get this thing out of my garage!....LOL!

 

[KyHeadhunter]

Ok, here are the pics I promised earlier. The final place I found chewed was in the K1 starter relay harness between the engine block and the hydraulic tank. It was a real nightmare to try to get to without pulling the entire engine harness out of the machine. I didn't have continuity between the harness plug and the relay so I went digging in there and found a chewed spot about the diameter of a cigarette. When I cut back the protective jacket, I found 3 wires chewed in half!! Furry little b@$*%ds!...LOL! I took the pics after I cut the jacket away. I would very much like to thank everyone that helped me to complete this project!! You all helped me more than you could ever know!!! Thanks again, Jim


http://i174.photobucket.com/albums/w105/kyheadhunter1/DSCN0626_zpsbf092d44.jpg

http://i174.photobucket.com/albums/w105/kyheadhunter1/DSCN0627_zps260e6290.jpg

 

[Deon]

KyHeadhunter,
I'm glad you finally got to the end of all this. You are a patient man. I don't
know how we can keep those furry guys out of our machines, but they are bad
news for sure. Thanks for replying with the results. That is what we all like to see.

 

[KyHeadhunter]

Me too, Deon and your right, it takes patience to track down electrical problems. I told the neighbor that I thought this happened because he left the hoe parked out in the field for a couple weeks, instead of in his barn where the mice have other things to eat. It was my pleasure to post up my findings too as without everyones help on here the job would have been a whole lot harder. Especially you Deon, thank you again for posting up that link to the schematic.

 

[werfymmot]

I have a similar starting problem that I thought was a weak battery problem as the over winter battery Voltage was only 12.0 V..
I will also be checking the wiring harness now.
thanks for posting.

 

[Paul Cote]

John Deere 210C backhoe 1989 won't start and won't crank. Power to accessories weak. Suspecting bad contact so check the 2 relays in the side panel. They tested fine. Now I am trying to find instructions to bench test the logic module. I see the link above to the TM1496 pdf but have no clue how to get to it with omnihost.us . They want user name and password?.....Paul

 

[Tinkerer]

It is a locked file. Deon posted the link and he most likely has the account user name and password. I would guess you would have to start a private conversation with him for information about it. I doubt he will share his username and password but, he may be able to copy the info you need and post it.

 

[Delmer]

I don't think the Deeres of that era needed the logic module to start or run, it ONLY turns on the warning buzzers. That's a relatively simple starting and running wiring setup, there is a start relay and accessory relay which I assume are the two you checked, how did you check them? the voltage coming in and the voltage coming out under load are the only things that would matter to me. On another "C" the 11 Red wires are the power from the battery to the relays and on to the 'ignition switch" 11, 11B, 11C. If you have an 11 Red at those locations that should give you a start, if you don't have an 11 Red, then find which one is hot and it will be similar at the other two locations.

Don't suspect something harder than it is, start from the most common, battery connections, weak battery etc.

 

[Paul Cote]

I wish it were true that there was no module unfortunately this machine has a logic module. JD part website list the module as part number AT107670 . The logic module is sitting on my table with that part number on it.waiting for me to bench test it and move on or buy a new module for $471. I checked the relays(neutral start and park relay by putting an ohmmeter across the coil-54 and 56 ohms. Then put voltage across the coil and check the resistance of the contact-0.5 ohms. Tried jump starting with my truck to no avail. Unfortunately the issue is beyond the battery. There is another relay under the hood that go to the starter. I assume it is a starter relay but JD calls it "accessory relay". I would like to be able to test that relay as well but not sure how. I do have power to the battery terminal on the switch.

 

[Paul Cote]

I believe I was in error on trying to get the link to TM1496. That is for the D version. The link I am looking for is TM1419 which is for the C version of the JD backhoes.
Has anybody purchased a pdf of this or similar from an online source that is reputable?

 

[mg2361]

Maybe this will help.

 

[Paul Cote]

Thanks for that page. It will be helpful. Would you happen to have the "logic module bench test page" I believe it might be 9015-00-72 ?

 

[Delmer]

I wish it were true that there was no module unfortunately this machine has a logic module. JD part website list the module as part number AT107670 . The logic module is sitting on my table with that part number on it.waiting for me to bench test it and move on or buy a new module for $471. I checked the relays(neutral start and park relay by putting an ohmmeter across the coil-54 and 56 ohms. Then put voltage across the coil and check the resistance of the contact-0.5 ohms. Tried jump starting with my truck to no avail. Unfortunately the issue is beyond the battery. There is another relay under the hood that go to the starter. I assume it is a starter relay but JD calls it "accessory relay". I would like to be able to test that relay as well but not sure how. I do have power to the battery terminal on the switch.

Assuming this is the same logic module as other "C" deere backhoes. There is a logic module, it just doesn't have anything to do with starting or running, it is for turning on the warning buzzers like I SAID THE FIRST TIME. Go ahead and buy another one if you don't believe me, or test it to your hearts content.

If it was me, I'd trace the wires and check the VOLTAGE coming out of the relays, and on down the line, ohms can be deceiving, volts don't lie.

 

[Paul Cote]

Thanks Delmer for coming back and clarifying. I miss interpreted what you said the first time. I get it now and much appreciate you coming back on this. I will go forward with tracing the wires.

 

[Delmer]

A simple way to do some tracing and voltage testing is to make up some test leads with alligator clips and some old extension cord wires, then you can put one on the small terminal on the starter solenoid, sit safely in the seat of the cab and turn the key to see if it's getting power. If you get no power then you can supply it with power if you have the dash open and see if the starter spins. Move to the positive battery terminal, repeat, then move to the next most suspicious part of wiring. Lots of fun ways to test. A "Power Probe" does the same thing more convieniently if you want to spend the $$$.

 

[mg2361]

Here you go. Also, Delmer is correct. Logic Module has nothing to do with the machines ability to start. You should be following the schematic I provided earlier to find your root cause. If you have a volt meter, if the fuse is good, start at the"S" terminal of the starter and work your way backwards toward the battery through all the components listed until you reach 12 volts. Don't forget to measure voltage at the grounds of each component as well (relays, starter). If you measure voltage at the ground side of anything you have a bad ground. Are the batteries good? Cables good?

 

[Paul Cote]

210C is now running after the help from mg2361 and Delmer. Thank you for getting me off the logic module trail. Found the ground battery cable terminal cracked. Then found a bad ground on the starter relay. Now the machine had lights and cranked the engine but no start. Then found a bad fuel solenoid fuse. All is well with my machine now. Again thanks for the help.

 

[mg2361]

That's great news. Good job Paul!