Guys.......I've installed an electric aerial into my EL Futura (second hand from a fairmont) and am using 2 SPDT relays to reverse the motor (up/down). So with the radio off the antenna goes down and with the radio on the antenna goes up. I'm using the original car switch to do this (got one off ebay). However, when the aerial fully extends or retracts I have to hit the switch to cut power to the unit otherwise the motor keeps running (not nice!!). So the question is what should I use to automatically turn power off to the antenna at full height or when retracted????? This function is normally controlled by the high series BCM (Body Control Module) - my car has the mid series.

When you say the motor continues to run does it just keep running solid, because I know in my Fairmont it runs for a little bit after fully lowered,say 5 seconds maybe, hard to judge that as always feels like it runs for ages, but just got use to it.
By the way mine is a fairmont, and if it's not meant to do this, be good to know why.

Edit: just reread it and realised I'd missed the part about the switch.
what happened to the delete post button? bah...

check out the technical doco on installing an antenna documents.php?d=69 the switch is probably the easiest and cheapest option. i've got a XR6 and just did the climate control conversion and upgraded the bem and it had all the wiring for the factory antenna. but before that i installed the factory premium sound and kept the manual antenna.

Thanks OZBMX............my aerial runs hard after 5/10 seconds and won't shut off. I think your's works ok then.

magna......Thanks for the link. I have checked it out and seems that I will just have to press the switch to stop the aerial on up/down cycle. I thought there might have been some current sensing device around that would do the trick........might keep looking for that.

Cheers