two questions about antenna wiring that i've not been able to find info about by searching...

i'm installing an aftermarket head unit:

1. there are two antenna leads that connected to the factory head in my '99 M3. one big one, which will obviously connect to the adaptor that i got, and a second, smaller one, which i don't know what do with. do i just leave the smaller one hang, or do i need another adaptor to connect it to something?

2. i got the antenna adaptor for the amplified antenna that's in my car, so it's got an extra wire coming from it with no label. do i want to wire that to the power antenna lead on the aftermarket head?

thanks in advance for the help.

I'm not completely sure but i know that you may not use all the wires that come in the harness

the first pic is the antenna leads in the car. the large one goes to the antenna adaptor that i got -- where, if anywhere, does the small one go?

second pic is the antenna adaptor. the larger antenna plug goes to one end and the other goes into the head unit. i want to confirm that i should wire the red wire to the power antenna lead on the head unit.

thanks much!

bump

yes it does. the red wire on the antenna adapter goes to the power antenna out wire on the radio.
Don't worry about the same one. It's for diversity antenna i think.
Bmo

You only need one antenna, the VW style one (larger). Don't worry about the second one. I could be wrong, but I don't think your car needs the amplified adapter. I believe the antenna amplifier wire is @ the harness, not the antenna itself. Unless someone else corrects me here, I would suggest trying the regular VW adaptor (much smaller).

I assume you also got the wiring harness?

You only need one antenna, the VW style one (larger). Don't worry about the second one. I could be wrong, but I don't think your car needs the amplified adapter. I believe the antenna amplifier wire is @ the harness, not the antenna itself. Unless someone else corrects me here, I would suggest trying the regular VW adaptor (much smaller).

I assume you also got the wiring harness?

That depends on his year. His 99, like mine, will have better reception with that "powered" antenna adapter installed :)

That depends on his year. His 99, like mine, will have better reception with that "powered" antenna adapter installed :)

What about for a '97 M3 with the HK system? I'm planning on using the simple VW antenna adapter instead of the adapter with the red wire. Will reception be compromised by using the simple VW adapter? Sorry for the threadjack. Thanks.

While I was in my 95 325 today, I noticed when I had my headunit installed, the POS installer cut the BMW antenna output and crimped on something else, and then plugged that into my pioneer 6800. I could not figure out why my reception was so awful after the headunit upgrade.

Never again will I take my equipment anywhere, I am fed up with the car stereo business's they are all shady! Of course I havent been everywhere but I am also sure you understand my frustration, why is buying car stereo equipment second only to buying a car in terms of aggravation and shadiness? Maybe im just unlucky..

Do it yourself, and youll know exactly what your getting, and if you screw up, youll know it and learn how to fix it later.

I just installed a Sony GT400 HU, which is supposed to have good reception based on the specifications. I used the powered adapter, the one pictured in the thread above. I left the small stock coaxial wire disconnected -- the one that may be for the "diversity antenna," used the adapter for the main coaxial antenna wire, connected the red powered adapter wire to both the HU power antenna lead (which the HU instructions say can be used for either an amplified antenna or a power antenna) and ALSO to the power antenna wire from my adapter harness.

Should I not have also included the connection to the power antenna wire from the adapter harness? I figured this might go all the way back to the rear of the car and might be important and could do no harm.

I get only 4-5 stations, but I receive them well. The stock HK HU probably brought in 8-10 stations, not all of them well.

Philip Bradley

I just installed a Sony GT400 HU, which is supposed to have good reception based on the specifications. I used the powered adapter, the one pictured in the thread above. I left the small stock coaxial wire disconnected -- the one that may be for the "diversity antenna," used the adapter for the main coaxial antenna wire, connected the red powered adapter wire to both the HU power antenna lead (which the HU instructions say can be used for either an amplified antenna or a power antenna) and ALSO to the power antenna wire from my adapter harness.

Should I not have also included the connection to the power antenna wire from the adapter harness? I figured this might go all the way back to the rear of the car and might be important and could do no harm.

I get only 4-5 stations, but I receive them well. The stock HK HU probably brought in 8-10 stations, not all of them well.

Philip Bradley

there is a power turn on for the antenna, so i think the proper wiring is as you have done it. i did the same, iirc. overall, the reception in my M3 has always been poor compared to other "more conventionally antennaed" cars, e.g., my volvo with extending mast on the driver's a-pillar...

my other problem is that i'm located roughly 1/2-way between philadelphia and baltimore, so i get stations from neither city very well. the only reliable stations for me are broadcast out of wilmington, de.

I believe the smaller one is for the am reception in the stock head unit.