At 08:33 PM 8/31/2007, James AYRES wrote...
>I have bought an after market radio in my 1985 Vanagon that came with
>a
>factory cassette player and am puzzled how to hook up the ACC line
>from the
>new radio.

When on, the radio will draw almost all of its power from the battery
(constant power) lead. From your question, it appears you've already
identified a suitable source for that. The ACC lead just signals the
radio that the car is turned on, and turns the stereo on
simultaneously. It doesn't really draw very much power at all. Use a
meter to find a fuse which has power with the ignition on, but none
with it off. You might also want to check if it has power when starting
- some circuits are powered through a load reduction relay which cuts
power when starting. That can be hard on a stereo.

Some of the fuses may have empty spade (AKA "quick disconnects")
connectors in back to which you can hook. If you can't find one of
those, Radio Shack sells special spade fittings which will add a tap to
an existing one (
http://www.radioshack.com/product/index.jsp?productId=2103503 ). Less
preferable would be to use a tap connector (like those commonly used to
connect trailer wiring) to tap into an existing wire.

I don't know for sure on an '85, but on an '81, fuse 12 is ACC
switched, powers the horn, and isn't cut off by the load reduction
relay.