Help with 2003 7-series seat controls in my hot rod

[Jamieson]

Howdy,

I am building a '73 Dodge Challenger hot rod. Because I value my spine, I bought a set of '03 BMW 745Li seats instead of using OEM style seats.

Now I'm trying to figure out the simplest way to operate the seat controls; I have the center console with all of the seat adjustment buttons. However, I cannot figure out how the seat control wiring is connected to each seat.

Using this forum I found a link to some wiring information which has been very helpful (http://spaghetticoder.org/bmw/wds/). The front seat controls have wiring ribbons that attach to a small computer inside the console. According to that link, that computer is called the "BZM", its seems that the BZM needs to connect to the "CAN BUS" (not positive what that is) and that in turn operates the seat motors.

Each of my front seats has computers mounted underneath it. I have wiring connectors with pigtails for all of the computer connections but do not know where they connect when they leave the seat.

Basically, I am looking for the simplest way to make the seat controls function outside of the original car.


If anyone has ANY tidbits of relevant information I would be very appreciative.

Thanks!!
Joe

[02325]

A "CAN BUS" is 2 wires that operate objects on different frequencies. Basically these 2 wires cans control 100 different things at different times. It keeps the wiring harness down.

All I am gonna say is good luck on the wiring. The seat modules dont just work off a simple 12V power and a ground.

[Jamieson]

Thanks! The reply is much appreciated. I'm expecting this swap to be moderately difficult, but I'm sure it can be done. I just have to figure out how much of a BMW I need to swap in to make the seats work.

[m series s10]

I have the seats and switches out of a 2004 745 and was told i might need the entire vehicle harness and another control module. I'd love to work together and get this figured out.

Can bus systems are data wires (similar to ethernet cable from a computer to modem). They send information from the switches to the control modules which tranfers to info into voltage out to the coresponding motor. I was originally told that the "can-bus) connection went from the switches to the seat modules (the ones mounted under the seats). that led me to believe that if i had the seats and the switches, all i needed was 12v power and ground and I could get the seats moving. Apparently, there is another control module and their might be alot more wiring involved. which isn't a problem as long a there is a proper diagram out there.

[m series s10]

I have taken apart one of the seats and i have pinned out the wires for:
Forward/backward
Knee bolster
seat bottom up down front
seat bottom up/down rear
back rest bolsters
detroit lean
upper detroit lean
head rest up/down
fans in back
fans on fanny

I can send you the wire colors. I think they are the same for pass& drivers
They are all 12v reverse polarity but the limit switches are on separate circuits. I am going to try to build a transistor type switching network and
see if i can utilize the factory switch assembly.
Sen me a private message here if you would like the color codes.

[Rhuddles]

This is lifesaving! I’m weeks into installing 2005 7 series seats into a 65 fastback mustang. I have the whole harness and center console controls, but can’t find wiring information. Did you find a source?