1988 BMW 528e Power Antenna Problem

I just installed a Sony CDX-M620 into my 1998 BMW 528e, with a telescopic power antenna.  The tuner works fine, but when I set the source to "CD", I think the Sony unit is cutting the power to the antenna, bringing it back down, and (I think) the BMW cuts power to the speakers when the antenna is down.

I tried disconnecting and reconnecting the antenna remote lead while the receiver was in "tuner" mode to troubleshoot. When the ANT REM lead (blue on harness to white on BMW) was disconnected, the antenna would telescope down, and the speakers would stop working... when I reconnected the lead, the speakers started working again.

Did I wire something wrong?  Is there a way to keep the antenna up at all times when the radio is on? Can I bypass the mechanism that supposedly turns off the speakers when the antenna is down?

Use the " REMOTE TURN ON LEAD" wire for your power antenna  instead of the " POWER ANTENNA LEAD" wire . This way the antenna will always stay up regardless of the source it is switched to. Good luck and if you need more help just post.

Duh, I forgot about that.   But what lead should I use to power my sub amp then?  I'll try to splice the wire to run to both the power antenna and the amplifier... maybe that'll do the trick.  I'll post again whether or not it worked.

Thanks for the response. 

That's the ticket !! Use the remote amp turn on lead for both the antenna and the amplifiers. Most of the time you can power up to 2 peices of equipment before if starts shutting off and turning back on intermittenly ( hope I spelled that right ). If the remote wire has too much on it , then you will have to use a relay to power the amp or the antenna.

Good deal, everything worked like a charm!

Now the next problem... how to get amp wires through the firewall and through the trunk of this car.   The back seats do not drop down, and there isn't an obvious place to drill.

When I wired my '98 Corolla, it was easy - just propped up a few panels, ran the wire under them, and when I got to the back seats, I just folded them down, ran the wires around, and strapped the amp to the back of the seats.  No drilling, no worries.

Have you done any installs on any late model BMW's?  The side floor panels on the BMW aren't easily removable like the Corolla... and in the BMW, the space between the cabin and the trunk is separated by a non-foldable back seat.  The firewall is another thing - I'll just have to get lucky with that one.  I hope there's a simple answer to this...

Jeremy