So far so good with my ongoing installation. I've had little problems that I've managed to find and eliminate, now after final amp-rack wiring I have this new one. Argh.

I'm using a Bosch 30A relay attached to my Clarion's Remote-ON which then triggers both my amps and two fans. The problem right now is that when I remove the key from the ignition (which should shut everything down), my power antenna starts having a fit.

I have yet to take my multimeter out to the car (it's bloody freezing and I don't have anyone else around right now to power down the system while I use the meter). The antenna just makes nasty ratcheting noises - it doesn't extend when powering down. I suspect it's getting a bit of voltage but not enough to cause it to go up.

The antenna works fine when the system is powered. It goes up and down as I switch in and out of tuner mode on the head unit.

When using a relay in a circuit that isn't designed for one, apparently you should place a diode in parallel with the coil. I have such a diode and it's in parallel with the coil - the correct end of the diode is also connected to the proper terminal (the one receiving the remote +12v). When not using a diode, apparently you can have negative voltage go back through your remote line as the coil loses its charge - which is bad for all sorts of transistors, etc..

Anyway, I suspect that I'm having a problem with this voltage and it's somehow going through the head unit and back out the antenna line. The antenna makes noise for a little longer than I'd expect however.

If I unplug the remote connection before shutting down the car, the problem doesn't occur. If I don't use the relay, but connect the Clarion's remote directly to the amps, the problem also does not occur. I think I'm looking in the right place. :)

One thing that might get rid of this problem is using the empeg's Remote line to trigger the relay, but I don't relish digging into my dash again. Plus if there is a negative voltage spike, I certainly don't want it in the system. :)

Anyone have any experience with relays in this type of install? Any suggestions welcome - even if suggestions for additional specific troubleshooting steps.

Bruno