We need someone with an LCI X3 to lift the rear seat cushion (four plastic carseat clips come out, and then the seat can be lifted, no tools required, takes 60 seconds) to see where the wiring goes. Two photos would be great.

We know that the replacement X3 rear seats from BMW all have heaters installed (and this is where the idea that all seats have heaters in them may have come from, if it isn't true).

Years ago, a US car manufacturer used to charge extra on a new car for back-up lights. However, the tail light lenses were the same on all models, and they all had the sockets. If you didn't pay for back-up lights, you had to go and buy two 1156 bulbs, and then they worked fine. It was just too expensive to make taillight assemblies two different ways. This was not publicized, of course, but factory and dealer employees knew it. My challenge is here, I need to know where the leads come out of the seats, as BMW may have put the heater elements in there, but they didn't run the leads out past the upholstery. I just don't feel like pulling the upholstery off on a chance.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue