For Jochen

[central3 31]

[jochen 4]

That's a new-generation radio with programmable tuner, as fitted to E46 cars from 2001 onwards

The antenna tuner is also a new generation antenna tuner, looks like it was made in March 2003

The build date of the antenna tuner coincides with your car (your car was built 04/2003, and is a E46 330i Saloon M54 Europe Right hand drive N)

So everything is right

If reception is still poor, check the following:

1. Antenna amplifier is tightly bolted to the C-pillar (ground issues)

2. Antenna amplifier has got 12V on the white wire when ign is on

3. Antenna coax cable is tightly fitted to the antenna amplifier

4. Antenna coax cable connector is undamaged and is correctly plugged into the radio

5. Try a different radio to compare - maybe the tuner in the radio is poor

6. Try your car next to another E46 in the area with same generation radio system, and compare received signal strength levels (in the radio service menu)

[central3 31]

Thanks - I checked suggestions 1,2 and 3 - all ok.

When checking I noticed that (with the radio on) there was almost no difference in reception quality when I unplugged the antenna coaxial lead. Reconnected and unplugged the power lead - absolutely no difference in reception quality. Reconnected and unplugged the multi pin plug (that connects to the window wires) - again absolutely no difference.

Suggestion 4 - before reinstalling the factory HU I was running an Alpine - I could get 3 or so stations but the quality was not good. Does this reduce the odds of my problem being with the OEM HU and perhaps point to a problem with my antenna amplifier?

I have spent most of the day on this and conclude that the only problem I have is is very poor reception. I ended up installing the band converter as with it I get another 2 stations but very weak - what do you think is happening here?

[jochen 4]

Thanks - I checked suggestions 1,2 and 3 - all ok.

When checking I noticed that (with the radio on) there was almost no difference in reception quality when I unplugged the antenna coaxial lead. Reconnected and unplugged the power lead - absolutely no difference in reception quality. Reconnected and unplugged the multi pin plug (that connects to the window wires) - again absolutely no difference.

Suggestion 4 - before reinstalling the factory HU I was running an Alpine - I could get 3 or so stations but the quality was not good. Does this reduce the odds of my problem being with the OEM HU and perhaps point to a problem with my antenna amplifier?

I have spent most of the day on this and conclude that the only problem I have is is very poor reception. I ended up installing the band converter as with it I get another 2 stations but very weak - what do you think is happening here?

Your comments indicate a problem with the antenna cable or antenna amplifier

Note that a band expander will always make reception worse due to the reduced sensitivity and reduced selectivity that a band expander causes.

Check reception as follows:

Insert a 1m to 2m length of any old wire into the center pin of the antenna socket of the radio - a bit tricky as the SMB connector uses a small center pin.

The piece of wire will act as a temporary antenna

Compare reception to previous situation

If better, then the coax to the antenna tuner, or the antenna tuner, is damaged. Look for damage due to band expander fitting.

Now reconnect the antenna coax at the radio and connect the 2m length of wire to the center pin of the coax cable at the antenna amplifier. Does reception improve? Is it about the same as when the wire was connected to the radio directly? If so, coax is OK

If no reception, then antenna coax is bad. Check antenna coax using a multimeter: should be open circuit between inner and outer.

It should show continuity along the inner from antenna amp to the radio

And the same for the outer from antenna amp to radio

If coax is OK and reception improved with wire at antenna amp end, then antenna amp or rear windscreen is faulty.

Check again for power at antenna amp

Unplug rear windscreen antenna connector and use wire on the pins and look for improved reception

Replace antenna amp if it is faulty

If antenna amp is OK, check rear window for damage to antenna elements. But unlikely if previous radio worked ok.

It rear window is damaged, repair elements using rear window element repair kit, or replace rear window

NOTE: ensure rear window has no metallic tint. Metallic window tine on a window with embedded antenna elements kills the reception