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Discussion Starter · #1 ·
Runs fine, but I've noticed recently it's getting slow to turn over (as if the battery isn't charging properly). Today I also noticed no headlights, no taillights, no reverse lights, no in-cab lighting or radio in the overhead console, and no warning beep when you first turn the ignition on. I don't know what else is failed...that's all I've found. I found one corroded red wire at the positive terminal so I assumed that was the culprit. Repaired that and replaced the battery while I was in there since it's almost 5 yrs old. Starts and runs fine (for now) but all of the above failures still exist, and I'm assuming it's still not charging. I've checked all the fuses I could find including the 40A cab pwr near the battery and the front power and rear power fuses in the panel. Dealer told me if I bring it by he might be able to get to it in a month, and if he needs parts it will be MUCH longer. Any help? Or similar problems? Thanks in advance.
 

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Runs fine, but I've noticed recently it's getting slow to turn over (as if the battery isn't charging properly). Today I also noticed no headlights, no taillights, no reverse lights, no in-cab lighting or radio in the overhead console, and no warning beep when you first turn the ignition on. I don't know what else is failed...that's all I've found. I found one corroded red wire at the positive terminal so I assumed that was the culprit. Repaired that and replaced the battery while I was in there since it's almost 5 yrs old. Starts and runs fine (for now) but all of the above failures still exist, and I'm assuming it's still not charging. I've checked all the fuses I could find including the 40A cab pwr near the battery and the front power and rear power fuses in the panel. Dealer told me if I bring it by he might be able to get to it in a month, and if he needs parts it will be MUCH longer. Any help? Or similar problems? Thanks in advance.
Is the alternator/voltage regulator functioning?

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Discussion Starter · #3 ·
Thanks for the response. I haven't tested the alternator because the failures are present before the alternator comes into play, e.g., the warning tone should beep as soon as I turn the ignition ON, and I should have lights and stereo before starting the engine. I don't have any of that. Make sense?
 

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Your post is riddled with observations, but if you want to resolve electrical issues it is best to use a voltmeter and know how to perform a couple of basic tests.

Quantitative data makes it easier to resolve issues.

Fuse can look good but what about the corresponding female connector each lead goes into. Thus the need to interrogate the wiring in a logical order.
 
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Is the Gator going through it’s POST operation (Power on self test) ? The display on the dash should illuminate.
 

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Discussion Starter · #7 ·
Your post is riddled with observations, but if you want to resolve electrical issues it is best to use a voltmeter and know how to perform a couple of basic tests.

Quantitative data makes it easier to resolve issues.

Fuse can look good but what about the corresponding female connector each lead goes into. Thus the need to interrogate the wiring in a logical order.
[/QUOTE

Awesome...I guess... I was a hoping to find someone on here who actually knows the 855M electrical system well enough to recognize (through my riddled observations) that all of these failures might be associated with a single circuit thereby reducing the amount of time I poke around with a multimeter looking for random and probably unrelated "quantitative data." Point me in a direction rather than providing elementary generalities about how to resolve electrical problems. I (sort of) appreciate your condescending input, but I really just need to know what time it is, not how to build a watch. I like this Gator forum because it has always been about like-minded tinkerers providing each other helpful shortcuts...because they've seen it before...not how to make each other look dumb. Thanks anyway.
 

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It wasn’t meant to be condescending and apologize if taken that way. Many times posters have the information but fail to disclose. I was hoping that was your case.

The first item I’d check/verify is battery state of charge (voltage) when off and again once running. Your new battery may not be as good as new should be. Both being healthy and function as they should eliminates a large portion of the circuit. From there a voltage drop test along the main circuits is a reasonable test.

Do you have access to a wiring diagram for you machine? Can you post or send a copy?

Do you have access to a voltmeter? (just trying to access what you have and knowledge in their use)

With most electrical issues it is very difficult to use symptoms as a viable way of pinpointing a root cause except for the most basic issues. Yours sounds a bit more complicated based on your description and thus surmise more detailed investigation will be needed

Given your statement about the corroded wire in an earlier post, it will likely require very diligent measurements across the connectors to pinpoint the problem(s) as not all electrical problems are visibly evident.

wish you luck and hope it is something very simple and inexpensive to fix.
 

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Mike, given the updated electronics on the newer models a Technical Manual for your Gator would help you greatly.

There are several different versions (categorized by the serial number or the last six digits of the PIN) -Product Identification Number on the 855 with different wiring/circuit schematics for each series. That said I would only be guessing on the next step or where to send you next.

PM Sent
 

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Discussion Starter · #10 ·
It wasn’t meant to be condescending and apologize if taken that way. Many times posters have the information but fail to disclose. I was hoping that was your case.

The first item I’d check/verify is battery state of charge (voltage) when off and again once running. Your new battery may not be as good as new should be. Both being healthy and function as they should eliminates a large portion of the circuit. From there a voltage drop test along the main circuits is a reasonable test.

Do you have access to a wiring diagram for you machine? Can you post or send a copy?

Do you have access to a voltmeter? (just trying to access what you have and knowledge in their use)

With most electrical issues it is very difficult to use symptoms as a viable way of pinpointing a root cause except for the most basic issues. Yours sounds a bit more complicated based on your description and thus surmise more detailed investigation will be needed

Given your statement about the corroded wire in an earlier post, it will likely require very diligent measurements across the connectors to pinpoint the problem(s) as not all electrical problems are visibly evident.

wish you luck and hope it is something very simple and inexpensive to fix.
Thank you sir, I'm on it. if I figure something out I will certainly reply.
 

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This is just a shot in the dark, but when my machine acted that way, I also replaced the battery. What I found while doing so was that one of my main hot wires was wedged between the battery tray and the front drive shaft. It had worn away the shielding and insulation, making a "wire to shaft" connection. Not enough draw to short anything out, but after a new battery and a repair on the wire, all is good again.
Good luck!
 

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Discussion Starter · #12 ·
This is just a shot in the dark, but when my machine acted that way, I also replaced the battery. What I found while doing so was that one of my main hot wires was wedged between the battery tray and the front drive shaft. It had worn away the shielding and insulation, making a "wire to shaft" connection. Not enough draw to short anything out, but after a new battery and a repair on the wire, all is good again.
Good luck!
Thanks, unfortunately I've been out of town and unable to investigate. I'll look into it!
 

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Discussion Starter · #13 ·
Eureka! Indeed the 855M has a "discretionary power circuit" used to isolate (power shed) several systems when it senses low voltage (presumably to protect computers). It's fused on F03 and the relay is K16. In my case the relay was bad and causing all my other problems in the OP. Thanks for the advice. Loved the wiring diagrams in the TM...the answers lie within!
 

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Thank you for posting the root cause and solution!!!

Glad to hear it’s been resolved and your back up and running.
 
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