Black plug car to Yellow Plug seat harness adapter

[Kudagra]

So I picked up some black sport seats out of a 2000 740i. They are the fancy 18 way heated seats. Im swapping over the truly hideous Lavendergrau interior in my 1998 740iL. Slowly. Anyway. I got these for $30 each. Then I realized the plugs were different and I had a journey on my hands.

I did many searches and I kept coming across people suggesting this thread: http://www.bimmerboard.com/forums/posts/493685

Anyone who does is a total jerk and not your friend. You should punch them.

That thread shows a guy just twisting a bunch of wires and "Finding out" what works. Well thats a load of crap. I don't like burning out expensive components. We have things like wiring diagrams in the service manual and http://www.bmw-planet.com/diagrams/r...8new/index.htm which has all the wiring diagram. THE PROBLEM with that last site is its European and doesn't show the yellow plug E38/39/46 seat plugs.

I cut the body side plug of the 2000 seat plug with about 8" if extra wire. I also found a 96 740 that was pretty stripped and chopped out the seat side of the power plug with as much wire as possible. I am mating the 2 together so I dont have to chop the harness on my car or on either of the seats. Plug n play.

Well I found where all the wires went. There is a wire on the seat side of the 96-98 seat that has no corresponding wire on the body harness. There are also other wires that just dont quite match on the 99+ harness. And there are some EXTRA wires.

Here is a list...so you no longer have to search. This is just the passenger seat. Ill do the Drivers seat next...but its pretty much the same.

98 2000


Pass (x279 x18092 x1570 Plug numbers in diagrams)


10 brn brn/blu 10
9 blu rd/blu 9
2 rd/wht rd/wht 6
1 pu/grn pu/grn 5
6 brn/blk brn/blk 8
1 brn brn 14
6* rd/ylw rd/ylw 13
7 blu/wht blu/wht 7
3* wht/ylw wht/grn 25
2* wht/blu wht/brn 23
1* brn brn(sm) 24
blu/rd (sm)- K Bus - Not used 15
5* pur/gry (Headreat light)


*= Large round terminals

I put the TERMINAL numbers next to the colors. I also did ENGLISH color abbreviations because...well...I dont read much German.




Brake clean dries your hands out.

[Mayorchuck]

Nice work Bryan. I need a set of these seats in grey. Delivered and installed please.

[nike32]

I just cut all wires on plugs and replaced them

[victoriabmw27]

Nice work Bryan. I need a set of these seats in grey. Delivered and installed please.

Haha I agree, I want to know where he got them!

[Kudagra]

If I find them Ill let you know....that they are at my shop. Ill even make conversion plugs. The pain in the ass about the drivers seat wiring is none of the manuals (paper or online) show the correct complete yellow plug for the 99+

Im about to try the connect and pray method.

[victoriabmw27]

If I find them Ill let you know....that they are at my shop. Ill even make conversion plugs. The pain in the ass about the drivers seat wiring is none of the manuals (paper or online) show the correct complete yellow plug for the 99+ Im about to try the connect and pray method.

Good luck! Might be a good write up opportunity once done.

[Mayorchuck]

Nothing on the news about a fire in Douglass County. Success?

[Qsilver7]

Anything on how you're getting around the different seatbelt tensioners and their wiring for the dual stage vs single stage airbag system...which goes along with the 3/99-up build date change to the yellow seat wiring harness plugs? Or can you swap the pre 3/99 tensioners onto the post 3/99 sport seats so that your single stage SRS system won't notice the change?

(tensioner is #1 in diagram if someone didn't know what I was asking about)

[AquilaBMW]

I have done this conversion a few times. Brian is absolutely right that there are two little wires remaining when going to pre-"yellow" seat harnesses. My biggest issue is pointed out by Q. The seat belt tensioner wires / connectors are different - when I did my conversions, I cut the wires and spliced in the newer tensioners. At one point, the driver's side SRS never came on again. Reversing the splice seemed to fix that. The issue is the wires are white and I wasn't sure which goes where.

Q's idea might be something to consider - maybe the Single Stage tensioners can just be bolted to the Dual Stage Seat?

[Kudagra]

They attach the same. What I found was the newer seat switch (S58 drivers side Plug x778 and S59 Passenger side plug x18165) both only had 2 wires. The older ones in my 98 each had 4 wires. Which is nothing even remotely the same as what is in the books or online. (95-98 3 wires, 99-2001 4 wires) I just plugged it in and went with it. I also just cut the old tensioner plugs off the old seats and swapped in the old tensioners. I guess Ill find out if I did it right if I ever crash it. I dont plan on it. .



I really hate the Lavendergrau. At least its not in a white car which Ive seen and is the worst color combination. At least with Aspensilver its kind of a whole purple hue thing going on.

Eventually the car will be repainted satin black and some e65 19" wheels.

I better get a job first.

[daytonatrbo]

Anything on how you're getting around the different seatbelt tensioners and their wiring for the dual stage vs single stage airbag system...which goes along with the 3/99-up build date change to the yellow seat wiring harness plugs? Or can you swap the pre 3/99 tensioners onto the post 3/99 sport seats so that your single stage SRS system won't notice the change?

(tensioner is #1 in diagram if someone didn't know what I was asking about)

That seatbelt extension. I'm betting that was a US only option

[Qsilver7]

That seatbelt extension (#2). I'm betting that was a US only option

(LOL)...okay, I laughed and thought you were probably correct. Then I ran part nbr #2 (it's a seat belt "adapter") through the database...and guess what...it's only offered in Europe!

Item #2 (seat belt adapter) in diagram above was only offered on Euro e38/e39 models...and is not listed on the USA side of the part database:

http://www.realoem.com/bmw/partxref....=on&showeur=on

[Kudagra]

Being a fat ass isn't a strictly American thing.

[victoriabmw27]

Being a fat ass isn't a strictly American thing.

The Germans are Europe's most overweight!

[Kudagra]

See...Being the best in the world has it's perks.

[spyderg0d]

I dissected the separate plugs from the main yellow plug.. That way, the heated seats were one plug. The seat belt tensioner was 1 plug. The occupancy sensor was 1 plug. The main power was 1 plug. They all run directly to the sensor or switch. No diagram needed. No wire cutting needed. Just take tiny nail or something alike. Pry clip to release the wire prong from the clip. The wire prong will fit right into the stock clip. Re attache the clip . Whualah. No mess. No hassle. SmRts pay off. (E46 seats to e36)

[Kudagra]

But I dont have to dissect anything if I want to switch back. It's plug and play now.

[deyrag]

First off, want to say this is the best thread i have seen so far for the seat swap involving the yellow/black issue. Thanks for posting.

Do you have the wiring finalized for the driver seat as well? I am just starting this same journey. Putting yellow connector E38 comfort seats with heat into a black connector E39 that had base seats w/o heat.

[Sroor9001]

Hope we got wiring diagram for driver side

[mooll]

Hope we got wiring diagram for driver side

there's one out there already for drivers side , passenger side is the harder side to do

[ConvGeorge]

One of my happiest e38 days was when I got to pull the old plug style seats the PO had hack wired into my car and replace them with a set with the correct plugs and the seat massagers to boot! Now I just need to get rid of the air bag light that is on because of the old seats.

[Bmwe39528i1998]

Does anyone have wiring diagram / pinout for black and yellow connectors on the driver's side?

[Mayorchuck]

I don't have time to look now but dig around in here:

https://bmwteka.com/

[Bmwe39528i1998]

I found your post from 5 years ago for that connector

https://www.bimmerforums.com/forum/s...eat-won-t-move

But i don't think it's right because X653 connector has 26 pins while the seat connector only has 25 pins
https://www.bimmerforums.com/forum/s...6#post30701516

I've spent a few hours trying to find it on tis without luck

- - - Updated - - -

I'll keep looking

[niklecce123]

It's sad that sites like Photobucket were the most common image hoster. All the pictures for this thread are gone, but they show on google. I wish Bimmer Forums would swap all the missing pictures with placeholder text as I hadn't realized there was originally pictures included here until just now... I'm currently on a mission to retrofit pre-facelift comfort seats into my facelift.


One thing that makes this issue overly complicated, is the crossover of people retrofitting into E39s and documenting those wiring differences. To add to this complexity, my facelift E38 was an early facelift built in 11/99