Coach Battery charging control??

[Professor]

I have a 2004 Lexington 255 with an Intellitec BD0 battery disconnect switch. When shore power is hooked up, the LED comes on, but it does not charge the batteries unless the "use" switch on the BD0 is pressed. The Coach and Chassis disconnect relays are in the back of the battery box, but what actually controls the charging voltage switching between shore power, generator and Chassis charging systems?

There doesn't seem to be any voltage regualtion control in the converter assembly (which does charge at 13.8 VDC), but several of the threads discuss a BIRD or SC107, etc. Where should I look for the device? There is a "black box" under the drivers seat, but it seems to have too many wires and the only label says to "replace the cover if removed"

Thanks,

[Professor]

Figured out the answer. The Parallax converter is a single mode charger and does not change the charging voltage. Took a bit of research to find, but I will replace with a three mode charger/converter.