4100 Not charging

[Cdash]

I have a 4100 that isn't charging. I was finishing mowing and it died like it was turned off. Found out that the battery died (would only hold 10ish volts) and replaced with a new battery and cleaned the terminals. The battery light never came on in the dash.

Couple weeks later I had the same thing happen again.... and never saw a battery light on the dash. Charged the battery and it was holding 12.8 (+) volts, so didn't appear to be the battery, but a charging problem. After reading forums and googling, I checked out some things and decided to buy the Technical Manual to assist with troubleshooting.

I have power everywhere that I am supposed to have power switched and unswitched. Alternator is pushing 48v AC at full speed (ok per the manual), and I pulled the ground off the frame and cleaned it up (it wasn't really dirty or corroded though).

The manual states to test the V1 & V2 diodes by checking continuity across the two terminals in both directions, and there should only be continuity in one direction. I didn't get continuity in either direction so I ordered two new ones, which I got today. I opened the new ones up and tested them in the same manner and I get no continuity in either direction on either of the new ones. I've tested continuity on different wires and connectors, so I can't see it being a meter problem, but I am at a loss. If it was one of the new diodes, I could see maybe getting one defective one, but not two... I even went back to my multi-meter manual to make sure I wasn't missing anything. Any ideas on what I may be screwing up?

So, I am suspecting that the diodes are not problematic and that leaves me with the voltage regulator. From what I read, it senses the draw vs charging output, and if draw>output, it energizes the wire that goes to the warning light (which would always happen with key in run and engine not running and I am not getting the light). I disconnected the plug to the Regulator and jumped hot to the terminal that outputs to the discharge light and the light works. So the regulator doesn't seem to be sensing and reacting when draw>output. Verified continuity to ground at the plug. I now have a new Regulator on order and will see if that fixes my problem.

Oh.... and fun fact - the Technical manual has the wiring positions incorrect on the X5 connector shown on the W1 main wiring harness - gear drive. They show 600 top left and 210 bottom left. Mine has 600 bottom left and 210 top left. It seems to be indicated correctly in the Circuit Diagnosis sheets though.

I'll post an update after the regulator comes in.

 

[al3]

Sounds like you are having a great time……..

You mentioned the 48 VAC at the alternator, what’s your DC output at the voltage regulator (with a low battery---manual suggest it won’t output DC unless the battery is slightly drained)? I'm assuming its zero and that's what you're trying to run down.

As far as testing diodes here’s a link to review. Sorry if you already know this; I find them a tad tricky as I don’t test them often.

How to Test a Diode: The Best Ways to Find Faulty Diodes


Saying that you saw no continuity in both directions might suggest selecting a too high Ohm setting. As you noted, its highly improbable that all 4 have failed open in both direction. You using a multimeter with a diode test function? You could switch to using just the Ohm function to cross check---maybe the meter has issues. I've had several where the circuitry goes bad.

At this point I’m thinking and typing. Just ideas.

Is it only possible to plug the diodes in one way, or can the anode/cathode sides be reversed?

The fuse F2 is intact?

The red power wire that connects to the starter stud and then goes thru fuse F2 to the regulator is sound? No corrosion on the stud/under the crimp?

Sounds like you reviewed this

4110 charging issue

www.greentractortalk.com

Sorry if this is brief or curt, got a project of my own. Looks like you’ve got a good handle on running it down.



Good luck

 

[5030]

I use the palm test on alternators. If it's warm or hot to the touch, it's charging. If it's cold it's not. Never screwed with one internally, I take it and have it rebuilt and call it good.

 

[rScotty]

The first test I do is at the battery with everything connected. When not running, the voltage should be in the 12.4 to 12.8 range - higher is better. An overnight charge followed by half an hour rest should result in a good battery showing closer to 12.8 volts.
Then I start the motor and measure the voltage at the battery. It needs to be above 13.5 vdc to charge efficiently. Normally it will rise with RPM and then at some point the voltage regulator will kick in and drop it back to the 13 to 15 volt range.


BTW, if you test the dash light and it is good. AND then you still do not see the dash light come on with key on and engine off .... that means either your ignition switch or the wire from VR to ign switch to lamp is bad. Jump the wire to test, and if still no light I'd replace ignition switch.

Some VRs do require that the ignition switch also be good.

No clue on what is happening with the diodes. If they all showed conduction in both directions then I'd say you were putting your fingers in parallel with the diodes.... a common mistake. But not showing any continuity is a oddity On the meter use the high ohm setting, not the continuity checking setting if it has one. OH! I know what it might be. Do you have a fuses in that meter? If so, one is blown. Flukes have fuses....

Later,
rScotty

 

[jd110]

Most likely the regulator is bad, but also check out the glow plug circuits. Have seen a few of those have a glow plug relay stick on and cause glow plugs to stay on all the tie. This over works the low amp charging system and causes failures. Hate to see you have repeat regulator failure due to bad glow plug relay/timer.

 

[Cdash]

Got and swapped out the voltage regulator this morning. The battery discharge light is now working. Checked engine running voltage at the battery and was at 12.6V (not charging).

Pulled the plug for the Glow Plug Module, checked and was at 13.2 V (and climbing). Looks like that is bad like others have experienced/suggested. I'll get that on order and should be the end of my saga until I dig into the leaking front axle seals this winter....

Added on edit - checked the manual and tested the Glow Plug Module - I found that it is NOT cutting the ground after 3 seconds like it is supposed to. I'll run with it unplugged until I get the part in.

 

[Cdash]

Final update - got the Glow Plug Module/Controller in, installed and tested. Problems are gone. For anyones future use - it was the Glow Plug Controller - part number M809173 - and it is located and attached to the radiator on the front of the tractor. This likely failed first and took out the voltage regulator.

The test to verify the old controller was bad, and that the new one was good is this: While still plugged into the controller, use a volt meter to touch the middle bottom (considering the connector latch the top) wire on the backside of the plug. You should have zero voltage with key off, with key in run position, it should read around 1volt for about 3 seconds, then jump up to battery voltage after the 3 seconds and stay there. My old one was not jumping up to battery voltage - meaning that glow plugs were not shutting off.