Need help with wiring yellow seat connector

[Bmwe39528i1998]

I finally got m5 seats and I'm rebuilding them.

Someone had cut off the connector, to use it with pre facelift black connectors. My vehicle is facelift, so I cut off the black connector and trying to get back to original, with yellow connectors.

Last step is connection the airbag tensioner. It has 2 black wires. And I don't know how to tell which one goes where.

On the main seat connector, they're pins 9 and 10, and on the tensioner connector, they're pins 1 and 2.

But it doesn't say which side is pin 1, and which side is pin 2? I'm not sure it even matters?

https://i.ibb.co/RpqdrR7/20240129-143957.jpg (https://ibb.co/kgtvbNM)
https://i.ibb.co/F4Nrm4q/20240129-143943.jpg (https://ibb.co/SwWj5w7)
https://i.ibb.co/c6KJDpZ/20240129-143935.jpg (https://ibb.co/48wWPDX)
https://i.ibb.co/zVHq3ng/20240129-143929.jpg (https://ibb.co/KxzTt0g)

I just don't want to mix up the wires.

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Doesn't help that the wiring diagram is incorrect and is showing improper colors.

The diagram shows one wire black and the other white, while both wires are black.

https://i.ibb.co/HhZHzjd/Screenshot-20240129-144850-Chrome.jpg (https://ibb.co/KKnrqJw)

[Bmwe39528i1998]

I must've looked at the older version diagram.
This diagram shows both wires as black.

https://i.ibb.co/5BTcx6N/Screenshot-20240129-164811-Chrome.jpg (https://ibb.co/vZ1zvH7)

Wire 1 goes to wire 9, and wire 2 goes to wire 10.

The only thing I can't figure out is how to tell which pin is 1, and which pin is 2, on that tensioner connector.

[JimLev]

It’s not marked somewhere in the connector, sometimes the numbers are in where the pins are.

[Bmwe39528i1998]

Yes tried that Jim, took apart the connector, still nothing.

I kept playing with the multimeter, and I think I figured it out.

Pins 9 and 10 on the main seat connector are shorted by design.

That's why it's irrelevant, which wire goes where, and that's why both twisted wires are the same color. They're shorted, so it doesn't matter how to connect them.

https://i.ibb.co/KFZBhz4/20240129-190514.jpg (https://ibb.co/XSB6Lk0)
https://i.ibb.co/QbvvVJQ/20240129-190502.jpg (https://ibb.co/Fx441h3)

Hard to see, but there's a special pin from factory on pins 9 and 10.

[taz.]

Yes tried that Jim, took apart the connector, still nothing.

I kept playing with the multimeter, and I think I figured it out.

Pins 9 and 10 on the main seat connector are shorted by design.

That's why it's irrelevant, which wire goes where, and that's why both twisted wires are the same color. They're shorted, so it doesn't matter how to connect them.

https://i.ibb.co/KFZBhz4/20240129-190514.jpg (https://ibb.co/XSB6Lk0)
https://i.ibb.co/QbvvVJQ/20240129-190502.jpg (https://ibb.co/Fx441h3)

Hard to see, but there's a special pin from factory on pins 9 and 10.Yes, for connector X10217 pin 1 is type E and goes to the ignition circuit, and pin 2 is type M and goes to ground.
They should match the shape of the ones in the yellow connector from your picture.
If not, take a multimeter, set on ohms, and check which pin grounds.
I can't remember right, but they should be marked inside the tensioner connector.
https://uploads.tapatalk-cdn.com/20240130/fed621e291b348de3598f4bdf7d3bd0f.jpghttps://uploads.tapatalk-cdn.com/20240130/3144440dfd94d7e4eaa5634ea0c73e75.jpg

Sent from my SM-S918B using Tapatalk

[taz.]

Don't you have another bmw, an x53 or a 528i, if I remember correctly?
Just check with a multimeter on one of the other bmws, which pin goes where.
The wiring should be the same for the tensioner.

Sent from my SM-S918B using Tapatalk

[deyrag]

One thing to be careful of is the tensioners are different between pre and post facelift. Make sure the previous owner did not swap them along with the connectors.

some good info about it in this thread

https://www.bimmerforums.com/forum/showthread.php?1578120-Successful-Sport-Seat-Swap-Using-Seats-With-Older-Black-Connectors

[Bmwe39528i1998]

Yes my friend. I had 1998 528i, loved the car, but was too boring. So I sold to a friend and drove it across canada. Then bought the 540i 2002 I have right now. Also have x5 2002 3.0 :)

I did check with the multimeter, and that's the thing, both wires are shorted, so multimeter is useless. But like a mentioned in my previous post, since the wires are shorted by factory, it doesn't matter how to connect them.

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Yes good point about the tensioner.
It's the right one, I.e. post facelist tensioner. Now just gotta put the seat inside and enjoy m5 seats finally!