Radio antenna

[doggee]

Where is the radio antenna? I figure it is in one of the windscreen pillars.

Just got a new radio/cd and can only pick up fm.

Maybe my antenna is not connected properly.

[M3wannabe]

Your antenna is part of the rear window demister.

Chances are that your new head unit is not powering up the antenna booster module that lives behind the rear passenger side (Australian) pillar trim.

[K73]

my e36 has it running around the front screen glass. M3wannabe is right as well, rear demister. we had a new screen fitted and lost all reception

[doggee]

Thanks, m3 wannabe

You could be right, but i found a coax lead under the rear headlining rhat wasn't connected to anything, but it runs of to the right hand side of the car.

The annoying thing is i need to fix the headlining but can't do it till i get the antenna sorted.

[M3wannabe]

The power wire from the head unit to the booster runs under the passenger seat.

It is part of the loom that comes up behind the rear passenger side backrest, and is one of the few wires that continues upwards instead of passing thru a grommet in the rear bulkhead.


I'll do a quick search of my notes and see if i can find the wire colour.

[M3wannabe]

Ooops... you mentioned the COAXIAL cable..... hmmmm, not sure where that one goes, but I would assume it WOULDNT be with a power feed loom as that would create interference in the reception. So up under the headlining would be the obvious "BMW Quality" location....

[Bimrpwr]

the color of the wire is White. Look for it at the antenna module and at the Head unit.

[M3wannabe]

I believe it is the white wire on the factory stereo plug that powers the booster.

There is actually a module mounted on each of the rear pillars. From what I recall, the one on the passenger side is the one that the coax cable plugs in to.

I also believe that the white wire is used to power up the rear demister which is built into the same module on the passenger side..... which makes me wonder if the non-factory head unit will affect the demister when you turn it off.

eg: Head unit off = no power ariel 12V output = no rear demister power.

Maybe it would be better to relay the power to the module via the ignition??? That way, the module will work whenever the ignition is on.... and not whenever the stereo is on.

[M3wannabe]

Ah, you beat me to it :D

At least we have the same answer... PHEW!!!



Another thing to add....

The AM and FM antennas are not the same strips on the window. Each is a different pair of rows at the very top of the window. If one of the elements has broken, the ariel wont work as well. Its the same as when one of the demister lines has broken, it doesnt heat up

[doggee]

Was one of the wires broken and how did you fix it.

This is obviously the problem with my radio as the top demister rectangle on the left hand side has a little piece missingg

[M3wannabe]

The element can be repaired.... not sure how its done *properly* though.....

I would start by checking if the big module (with the coaxial input) is getting power, first of all.

White wire = power from stereo
Black wire = power from de-fog switch.

Check that the suppression filter on the other rear pillar is connected. It links the middle and lower element circuits, which are both connected to the big module.

Check the earth on the big module. The brown wire could be broken somewhere, making the circuit incomplete. You could make a temporary earth from the module to anywhere on the body, just to check if it makes a difference.

EDIT* Oops.... just noticed that you said "can only pick up FM"...... Who the hell listens to AM anyway??????:rofl:

The AM ariel is the group of 3 elements on the drivers side (australian) of the rear window. There should be a single element for FM about an inch above those 3. I believe the big module has AM and FM printed next to the corresponding plugs....

[Monty1234]

and to add one more thing, The module also handles the keyless entry function. IE The FM antenna is the antenna for the key to open the doors.

[doggee]

M3wannabe

AM breakfast radio is good here in Melb.

If I want to listen to prats I can do that at home with the kids.

S%#t, maybe I'm too old to own one of these cars and should have got a Japbox.

[doggee]

Couldn't afford the speeding tickets either, but could have lived with it.

[M3wannabe]

If I want to listen to prats I can do that at home with the kids.

I have noticed that too..... Stupid radio stations these days. Personally, i only ever listen to CDs....