I mentioned this in another thread regarding problems I'm having with the RTC clock on my Amiga 3000. When I have the daughtercard plugged in, I have a short between ground and +5V when measured with a continuity tester.
i saw the same thing on 2 A3000 DB. there's probably no short on your.
look in resistor mode, you should found something around 10 ohms. as said Castellen
