[Steve Castellotti]

hey all-

I'm trying to figure out if there's a way to trick a sony headunit
into letting me use its pair of rear AUX inputs, but it won't let me
select that source unless there's a CD or MD unit attached via Sony's
proprietary bus cabling. I'm wondering if there's a special set of key
combinations on the console to force it into AUX mode?

I'm using a Sony XR-CA430 car head unit in a marine environment,
where all the wiring should be permanent and not visible (e.g. not
front AUX). I'll have to replace the head unit if there's no way to
hack into that function.

I figure there has to some means of entering a diagnositic mode, or
tricking it by soldering the right resistor across a sacrificial RC-62
cable. I used to have an Eclipse player that "programmed" itself to a
chosen CD, and stop operating if that same CD wasn't inserted again
after being disconnected from power. It was supposed to be a security
feature but if you called them up with a locked player they'd tell you
what to press to unlock it. I'm hoping there's something similar here.

Does anyone have any ideas, or pointers to where else might be worth
asking?

Cheers

Steve