hello, sorry for my english.
i have e53 2003 with 16:9 navi, mb54 radio module in the trunk.

I installed Erisin ES3493B unit.

https://www.erisin.com/bmw-e39-e53-c...tion_p963.html

everything works perfect except the FM radio. very bad radio reception.
I changed 2 antenna amplifiers, one in the back side window



another in the rear window. nothing changed. when I connect another antenna, everything is ok.

i think that my oem FM amplifier is not activating, but +12 is coming to the amplifier. there is 1 socket on amplifier (3rd frome the left). but 2 wires are going into it. 1 is blue (ANT amp), 2nd the ibus wire.
9 and 13 pins



i have tried many antenna boosters with +12 wire connected to the blue wire (amp remonte)


still nothing.

i even tried to connect the unit directly in the trunk, without main cable and antenna extension.

I'm waiting for another adapter. but I think it does not help.


Who else has the same problem?

Thanks