Southwind Aux Battery switch

WHAT YELLOW AND GEEN LIGHTS !!???
I have a Southwind, with master switches over the main entrance door (no lights there) one for coach, other for engine and chasis related.
In e dash I only have a switch that bridges (via a big relay), both sides of the battery isolator, hence the coach batts helping with the engine starter, BUT NO LIGHTS showing!, or the actual switch has lights and myne are burned out?, is the stock switch btw.

As an added thought. With the switch on, the house batteries should be able to help start the coach. This is done via a electronic switch. You can tell if the coach batteries are being used to assist starting by looking at the green and orange right below the steering wheel. If while starting the coach only the green light is lit then the chassis battery is doing all the work. If the orange/yellow light comes on then the coach batteries are assisting the start.

I should had said it disconnects the battery from the camper's fuse block not the Chassis fuse block.

No just disconnects battery from your coach electric. The switch is in the compartment above the door but the solenoid that the switch controls is under the hood on the drivers side inside the black box that has fuses and circuit breakers in it.