Yes. That's what I'm calling the 15 ft. extension harness. In reality 6M is 18 feet, not 15.

The way it's installed now, the connector with 4 wires (40-pin female plug C) is plugged into the old radio (the one you said should be abandoned), and the other connector (40-pin male plug A) is connected to the BMW factory harness. That BMW factory harness used to be plugged into the old radio.

The other 2 connectors B and D (with the round pins), do not connect to anything in my car at this time, as there is nowhere for them to plug in anyways. I think they are a replication of connectors A and C, and they are there for BMW's factory setup for those radios that have the round pins instead of the flat pins.

I forgot to answer one of your questions from a couple of posts earlier about plugging the factory radio back in to test, and the answer is NO. I haven't had a chance to do that yet.

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Thank you,

Samer

2005 X5 4.8iS
1989 635CSi M/T