1998 bmw 740 il

HI guys this is bit out of my scope. I didn't get many of these at my shop. So here is what is going on, it does have the nav. The previous owner said the stereo was working. He disconnected the battery to charge it and when he reconected the terminals the radio didnt come on. The unit is not asking for a security code. When you turn it on and try to tune the stations it just cycles like no antenna. Both the tape and changer say error when trying to use them. From what I have read the tuner is in the trunk with all the other components. I did pop speakers at the amp that worked changed and tested fuses for what was listed on as radio and amp. I have pics of what is there I am trying to help a buddy get this figured out. Any help would be great!
I am pretty sure the file size is too large to post here. I can either email them or text them. My number is 330-475-9211 or email me at daniel.kouri.sr@gmail.com.
Thanks again guys

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Daniel Kouri

sounds like something not getting power, possibly something is unplugged. did you check EVERY fuse box? usually on a 7 series there will be at least two fuse boxes and sometimes three. one is usually by the battery where ever that is (trunk or hood), one is usually behind the glove box and sometimes there can be one under the back seat.

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Thanks,
I did check the one in the trunk and under the hood. I will look for a fuse box in those other locations. I can send you pics but the res. is too high to post in the message.

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Daniel Kouri

Find the Logic7 amp in the drivers side rear of the trunk. Remove the amp and look for a fuse under where the harness plugs into the amp.

If a battery charger or the battery were connected backwards, it will have blown the fuse in the amp.