I am going from bm24 to bm54 to make my MKIV and 16:9 setup complete.
Today the last piece of the puzzle, the adapter harness arrived.
When I connected everything and powered on the car, there was no sound.
Also all radio info is totally missing. I cannot select any source like CD, Tape or AUX.
I have coded the nav to bm54 using navcoder but that didn´t help.
But I can see the radio through navcoder.
Might try to disconnect the battery for some time, see if that helps.
Another thing is that the old bm24 radio seems to have 2 antenna connectors?
As seen in this image (not mine), the bm24 has a small connector on the left side, between the antenna adapter and the fastening nut.
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What´s that for? My bm54 doesn´t have it.
Navcoder reads:
Becker, 6 933 091, HW03, SW81, CI02.
april 2003