AFter much wrestling with the problem, I came to the conclusion that the only time I'd heard a contacter chattering away loudly was when battery voltage was low.... but why would there be any power to the contactor with the master switch off?? Would explain why some of the avionics boxes were misbehaving too.
Voltmeter check showed that the main bus had 13.8v with the master on, but 9.8 volts with it off!
Then I noticed that the diode on the battery connector went to the wrong side... bugger.. the first bit of wiring that I did, 9 months ago! Swapped the connector, and everything works perfectly!. The avionics have power, the lights, fuel pump have power, and it works!
great day!
Im more pleased with the fact that I figured it out without help, rather than the fact that it works...
