Never gave it much thought, but now that I do - my house and chassis are both tied to both battery lights (red and yellow). It uses a high current solenoid (24v coach) rather than an isolator which connects chassis/house/alternator output together once coach (alternator) is running.

If coach has been unplugged for awhile and I start engine and turn on shore power (or probably generator also) the inverters immediately ramp up briefly to a voltage high enough the red battery light will illuminate. Once I see that I either turn off engine or shore power. If starting and coach has been plugged in and in float mode, no battery light.

Had never seen yellow battery balance light. Changed monitor a few months back from the old original EM70 to the later EM70D (from memory but I think that's correct) and discovered during the changeout that the ground wire was not connected on the old unit. Don't know if this was intentional or accidental. Installed new monitor and now yellow battery balance light illuminates for a few seconds after engine start and then goes out. Assuming this is normal.