Hi there!

Just for interests sake: The system will not work if a fault is detected anywhere...I had one the other day that did'nt
want to pump over to the main..removed the sender on the sub tank and found that the float had come apart due to
our corrugated roads in Namibia. It cost a bit of fiddling to reassemble and crimping on the flloat arm to get it working again...

Hope this might help somebody someday...(If I remember correctly,we cut a flap into the carpet for easy access....)