Is the factory antenna compatible with aftermarket HU's?

[boy412]

I would have assumed the answer to be a resounding "yes" but the shop installing a new JVC head unit (KD-X80BT) says its not compatible. Something about a 5 wire system vs a 1 wire system?

Admittedly its been a while since I've had a head unit installed. The last time was in the early 90's when I had a new Nakamichi desk installed in my '87 iS. No trouble integrating with the factory antenna back then! Obviously things have changed a little bit since then.

I've seen some people install a window circuit breaker in the dash to turn the power antenna off and on, but is there a better way? It seems like such a simple thing to accomplish. I'm unclear on why a new HU would not be compatible with the factory Hirschmann power antenna.

[AndrewBird]

It is compatible. The guy at the car stereo shop doesn't know what he is talking about.

[boy412]

That was my suspicion. I'd like to go back armed with some facts, etc. All that is necessary for the antenna to work is a power lead, a trigger lead, and ground...yes? I don't know what he meant by a "5 wire system".

[jeffnhiscars]

I doubt the antenna gives a crap what HU its connected to

[AndrewBird]

The actual antenna wire needs to plug into the radio and then the harness on the radio will have an amp turn on/antenna wire. This wires tells the antenna to turn on. That is all you need.

[boy412]

Is there any chance that any of the factory antenna wiring (like power and the trigger) is routed through the factory amp? And if missing/disconnected would cause problems?

[StereoInstaller1]

That was my suspicion. I'd like to go back armed with some facts, etc. All that is necessary for the antenna to work is a power lead, a trigger lead, and ground...yes? I don't know what he meant by a "5 wire system".

I do...and I recommend you go get your car back before they hack the shit out of it...5 wire refers to door locks, there are no antennas ever made that have 5 wires...none.

Yours uses the white wire in the dash (1 of 2 if your car is Premium Sound) to run the antenna.

If you feel like the guy working on your car is capable, have him read some of the install threads.

Don't let your car get butchered.

Luke

[boy412]

I've been steadily un-butchering this car to the best of my abilities (and budget). It's come a long way already.

Forget the 5 wire question...that guy was smoking crack obviously (and wanted to sell me a new "Euro" antenna). I was just wondering if the trigger was routed through the amplifier wiring...and if the absence of the power amp would cause the trigger to not work? Sounds like that is not the case.

Starting to think something may be awry with the factory antenna wiring, since I'm told they are applying a trigger to the antenna and it won't power up. Or maybe something is up with the antenna itself. Bought it used (factory Hirschmann) here on the forums and did not have a way to test it.

Luke I wish you were in Washington DC. It would be great to have someone nearby that understands these older German cars and how to coax decent sound out of them. And a public thanks for all the great tutorials.

[AndrewBird]

There are separate turn on wires for the amp and the antenna. That means there are 2 wires at the stereo as well, though they might be spliced together up there from the factory. Make sure both are hooked up to your radio.

[ascendotuum]

I just installed a stereo in my E30 a week or so ago. My car did not have a factory amp, and it had the separate fader knob in the dash, so yours may be different. There was a white wire for the power antenna. It must run to a relay, because with power applied to the wire, the antenna goes up. When you take voltage away from the white wire, it goes back down. So it's getting power elsewhere. The white wire just triggers a relay I believe. I verified this by applying voltage to it with a 9V battery, and the antenna went up. I hooked this wire to the remote amp wire on my aftermarket stereo and it works perfectly.

Maybe the relay is bad? Or the power antenna isn't getting power?

[Vtec?lol]

^What? There are no relays involved.

If you have premium sound the amp and the ant should be spliced into the white wire. Every car I've had, had the amp and ant on the same white wire.

[StereoInstaller1]

^What? There are no relays involved.

If you have premium sound the amp and the ant should be spliced into the white wire. Every car I've had, had the amp and ant on the same white wire.

If you look more closely, you will see there are in fact 2 white wires connected together right behind the deck.

You are absolutely correct though, no relays in the antenna wiring.

[Todd Black 88]

I just installed a stereo in my E30 a week or so ago. My car did not have a factory amp, and it had the separate fader knob in the dash, so yours may be different. There was a white wire for the power antenna. It must run to a relay, because with power applied to the wire, the antenna goes up. When you take voltage away from the white wire, it goes back down. So it's getting power elsewhere. The white wire just triggers a relay I believe. I verified this by applying voltage to it with a 9V battery, and the antenna went up. I hooked this wire to the remote amp wire on my aftermarket stereo and it works perfectly.

Maybe the relay is bad? Or the power antenna isn't getting power?

Huh?

That's how shit works. You give it power, it does it's thing. You take it away, it stops.

[ascendotuum]

My bad. I was just assuming. My point was that there is a 12v constant, and a 12v trigger. If the white trigger wire doesn't go to a relay, then there must be a circuit board.

[StereoInstaller1]

My bad. I was just assuming. My point was that there is a 12v constant, and a 12v trigger. If the white trigger wire doesn't go to a relay, then there must be a circuit board.

Absolutely correct, inside the body of the antenna motor.