48V Charger not turning off - Deere eGator with Curtis controller

[khnitz]

I have a 2000 John Deere electric turf Gator and have issues with the battery charger not turning off after long periods of time charging the batteries. I should add that the batteries do take a charge from the charger during this time. The eGator uses a Curtis 1264-5403 controller.

Background (eGator1): I recently re-habbed this eGator (I'll call it eGator1, as I have 2 of them), and put new batteries in it (less than 2 months old). When charging the batteries, the Lestronic charger starts out at about 15A output, and will go down to <5A...but it does not switch off on its own even after ~24hrs. At that point, I disconnect the charger to hopefully not overstress the batteries. My experience with eGator1 is limited, so far, as I only got it back on the road a month or so ago.

Background (eGator2): We have been using eGator2 consistently for the last several years. The charging behavior was normal and behaved as expected (charger shutting off after 8-12hrs when completing a full charge). In the last few months, the charger started taking longer and longer to complete a charge...but it would eventually shut off. The batteries in eGator2 are 5 or more years old, so they are due for replacement. eGator2 is now in the process of being re-habbed, as well (moving all the running gear and eletronics to a cleaner chassis).

I have 2 Lestronic 48V chargers. One is an original JD charger, and the other is a generic Lestronic 48V charger where I changed the charging cable over to the JD-specific one. Both of them exhibit this "no shut off" condition when trying to charge eGator1.

Last night I did measure the voltage (at rest) across each of the 8 new (less than 2 months old) batteries in eGator1, and they all measured about 6.47V.

I will be double-checking the wiring connections at the charging receptacle in eGator1, specifically looking at the connections between the battery pack and the receptacle. I will also double-check the hour-meter connectons, as the charge-level bar shows faintly, even when the key is Off (when the key is On, it shows brightly).

I appreciate any suggestions and BTDT experience!

[khnitz]

Just an update: I plugged the LestronicII 48V charger back in to the eGator yesterday afternoon, and the charger shut off after a few more hours.

I will have to monitor the eGator over the next few charge cycles and see if things get more normal. If so, then maybe this behavior was just part of what I've read about new batteries needing longer initial charging cycles (though the ones I've experienced so far have been for longer than I was comfortable leaving the batteries on the charger).