Welcome to the forum.
Also worth noting is that when you are plugged into shore power you need to turn on both coach and chassis battery disconnect switches at the door in order to charge all the batteries from the coach converter......I am assuming your 1999 coach uses some version of the RV Custom Product BCC (Battery Control Cabinet) mounted in the engine bay.
It is a good idea to also buy a cheap digital voltmeter (multimeter) if you don't already have one and actually check voltage across each battery set (coach and chassis) when on shore power, with the switches on (coach lightly loaded). You should measure 13+ volts DC if the batteries are charging OK......if not then there may be a problem in the charging circuit(s) that needs to be resolved.
One other little item that fools many folks is that the Light on the coach disconnect switch will come on when you are connected to shore power, but that does not mean the coach batteries are actually being charged by the converter. You have to turn on the coach battery disconnect switch to actually connect the coach batteries to the converter output. I rarely boondock and usually always connect to shore other than when travelling, so my coach and chassis battery disconnects are almost always left on the entire camping season. Less wear and tear on the latching relays and no questions of if they are on or not.