My BMW E90 seat install

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Outstanding work.

Hard to be sure from your pic, but I wanted to ask about your installation.
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Is the ground term on the 555 is connected to the green wire? Only that wire, or is it actually connected to a chassis ground too? I can see the 555 output connected to the orange/green. Then for power, you picking it up anywhere in particular or just on the incoming 12v from the chassis? Is that smaller red/black wire the power for the lumbar and the bigger red/brown the main seat power?

Thanks.
 
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Outstanding work.

Hard to be sure from your pic, but I wanted to ask about your installation.
View attachment 3714129

View attachment 3714130

Is the ground term on the 555 is connected to the green wire? Only that wire, or is it actually connected to a chassis ground too? I can see the 555 output connected to the orange/green. Then for power, you picking it up anywhere in particular or just on the incoming 12v from the chassis? Is that smaller red/black wire the power for the lumbar and the bigger red/brown the main seat power?

Thanks.
So the diagram i have is a bit confusing but in reality it’s simple. The +12v and GND to the 555 chip can be your normal vehicle 12v (I did switched) and GND points. The output goes to the CAN_H (green/orange pin 2) on the bmw unit. This wiggles the can bus and simulates data traffic. CAN_L (green pin 3) gets tied to GND.

And yes you are exactly correct on the Lumbar and Seat motor power lines
 
If anyone is interested, the cushions will swap from passenger to drivers side.

I just did the set I have to help even out the wear. No problem.

In doing so, I did find that I believe there are heating elements in the cushions, even though there didn't appear to be any controls in the car.

Three wires go to a controller in the cushion, which the heating grid is connected to, and there is a seperate 3 wire sensor for something that goes to the cover.

This is the original passenger side lower cushion.
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Yah there was never (afaik) heat controls in the BMW seat, always console mounted or similar. I wired mine like the FJZ80 did stock and seems to work. Only downside is there is no auto timer off or heat limit off.
 
I'm not gonna fool with the heaters for now.

Here's what my timer looked like installed. I had removed the extra wires and the seat side of the connector was somewhat modular. I was able to make my connections close and keep everything tucked in the empty space pretty well. Just a wrap of tape to hold it in place.


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Those 3 red circles are the end of the heat shrink on the connections.

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I will probably re read some threads and look for information for the memory settings. I can't remember if anyone got that working.
 
First tried a 20v drill battery. Gonna hook them up to my fj40 battery tomorrow to try.

update - They work. just need to figure out the 5V Can bus wiring.

Also need to figure out if i have heated seats. I am thinking about pulling the leather cover partially off to get my eyes in the element. Do i need to use bmw switches to get them to work?
Hi guys, i just created an account on this forum hoping someone would help me resolve this issue, I bought a E92 power seat no heat just power and position memory using a 12v 40a PSU that i got on Amazon, I just want to use the buttons to adjust the seat to my liking, i was able to power it through the + and - but after a few seconds nothing, tried to power the green wire which is supposed to give the constant “on” signal but it didn’t helped neither, I’m intending to use your on/off switch if i have no choice, did anyone manage to get it to work finally?
Thank you in advance guys.
 
Hi guys, i just created an account on this forum hoping someone would help me resolve this issue, I bought a E92 power seat no heat just power and position memory using a 12v 40a PSU that i got on Amazon, I just want to use the buttons to adjust the seat to my liking, i was able to power it through the + and - but after a few seconds nothing, tried to power the green wire which is supposed to give the constant “on” signal but it didn’t helped neither, I’m intending to use your on/off switch if i have no choice, did anyone manage to get it to work finally?
Thank you in advance guys.
You need a 555 timer or similar to keep the canbus awake. My thread and others show it wired up
 
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