Re: John Deere 4100 won't charge battery
Well I finally received the tech manual today, too many pages in the Electrical system section and not enough time left in the day to go thru it all, so I did what most guys do, looked for the quick test/fix. After 3 hours of testing components and analyzing the schematics and not finding a bad part, I switched the "K7 Safety Relay" with the "PTO Light Relay" (because they look identical) and the charging system started working. Oddly enough, the PTO system appears to be working fine also. So my best guess to the problem is the relay was/is partially damaged from either the battery cell popping or the voltage surge and although it was still passing current thru it, it wasn't enough to turn the voltage regulator on to charge the battery. I also put the old voltage regulator back in and it works fine, $140 wasted.
If anyone needs any details to help troubleshoot your own problem, let me know, I'd me happy to share them.
John Deere 4100
54" Mid-mount Mower
5 ft York Rake
5 ft Grading Blade
PTO DR Chipper
50" PTO Snowblower