2000 GEM e825 blinks green then red when charging

Good batteries in 2000 GEM e825 do not seem to charge. when charging the BDI first flashes 12 times green and then 4 times red. Keeps flashing red, 4 times then a pause, then 4 times, etc. Can’t find this light series in the manual.
Batteries were at 85% and did not charge at all after 8 hours.
Any ideas?

You can download a troubleshooting guide at Delta-Q, if that is the charger on your GEM

QuiQ Charger - GEM Product Manual

This manual contains important safety and operating
instructions for versions of the QuiQ or QuiQ-dci charger / DC-DC converter installed on GEM brand vehicles (Model nos. 912-240x / 360x / 480x / 720x. Please read this information before using your Delta-Q QuiQ Charger. For manufacturer contact information and technical support resources, please visit delta-q.com/support

4 red flashes:

Charge timeout: the charge did not
complete in the allowed time. This
may indicate a problem with the
battery pack (voltage not attaining
the required level), or that the charger
output was reduced due to high
ambient temperatures.

Check all the battery connectors, be sure all are clean with no corrosion and are tight.

Make sure you have a heavy duty extension cord and good connections on ac.
4 flashes is “AC voltage out of range”.

Dave you are absolutely right, I copied the wrong box.

Thanks for the input. All fittings tight. correct ext. cord. This time battery at 70% and started charging. Green light blinking for some time, then went to blinking yellow and ended blinking green. Checked after a couple hours and display shows 100% charged. Batteries at 13v.
Maybe the charging problem was heat. I’m in Arizona and it has been 110+ all week.
What is the proper light sequence when the unit is charging? Does flashing green mean fully charged?
Cheers!