UFO behind seat.

[LesPaul]

I was installing a cd changer and was running the control cable to the trunk and I discovered a little square electronic box on the far left behind the rear left passenger seat. It has a lot of numbers on and was manufactured by Siemens. I wonder......could this be the main computer, or is it simply something else that BMW has put there to control another function?
While on the subject of main computer BIOS, If I find that I have the original "1995" bios, will it behoove me, to upgrade? I own a 1995 740i.
No real problems and I'd rather leave it that way rather than risk confusing my automobile. Is the upgrade completely plug and play? Is there anyone out there in BMW Land who has had my exact experience and can attest to success or failure first hand? If not, I'd be grateful to entertain related suggestions.
Some of the box's numbers are these. EWS/FSV 12v 66.12-8 361 945.9
5wk4 578 Siemens 315 mhz LX8FZV 83g00040.
Or am I reaching?
thank you in advance for an educational discussion.

[Torque]

That box is most likely your Factory Amplifier (at least it was there in 89-95 5 series).

[Forge]

behoove me

Whispers.. behoof :lol:

[Bear]

Factory Amplifier for stereo receiver in my 1988 750,was mounted in trunk, drivers side of car, and behind the carpeting that is against the left rear fender.

[325isBaby]

Your EWS Remote Control Module is what you found for EWS II. As the Part number states EWS/FSV 12v 66.12-8 361 945.9 The Main computer is not in the trunk. If you have any other questions, I would be happy to try to elaberate for you