[trjn]

2015 535i xdrive
napa comfort heated seats

I bought this car a couple of months ago knowing the driver's seat electronics didnt work. I thought it would be an easy fix with the change in either fuses, switch or module.

Current situation:
Memory works(mirror and steering wheel)
Heat works.
Lumbar support buttons work.

But other seat adjustment buttons do not do anything.

Troubleshooting steps:

- Changed all the fuses that are labelled for seats. No go.
- scanning with ISTA gives SMFA error, which points to module or switch error.
However, I can access all the seat movements from ISTA commands. ISTA also recognizes all the seat adjustment buttons when activated. I set the seat to position to my liking via ISTA.
- Bought a used driver's seat switch assembly, same issue. Lumbar support buttons work, but not the other buttons.

From studying the diagrams in TIS, I feel its the issue is either with the wiring or the seat module.
I doubt its a wiring issue because I can use ISTA to access all the motors and also ISTA reads the buttons when activated even though there is no movement of seats via button presses. But who knows.

For who have experienced such issue or did a seats retrofit, what would a logical next step?
Just change the seat module with a new/used one or try and trace the wiring to LIN bus?

Its my 4th BMW and have done a ton of retrofits in my BMWs and previous audi including changing individual seat motors and wiring to install memory seats in that car. So, I am pretty confident on doing the wiring, but would want an insight on what should be my next step.

[Trainwreck914]

Being that all the seat controls work using ista I would just source a used module at this point. I had an issue with my Bluetooth module when I purchased the car. Found a used one on eBay and replaced it. It worked. Just plug and play. The only thing is the vin # don't match. So I get an error in ista as well as an emergency call error on the dash. Not a big deal until I learn how to code the vin. Haven't really found out how yet.

[trjn]

Originally Posted by Trainwreck914

Being that all the seat controls work using ista I would just source a used module at this point. I had an issue with my Bluetooth module when I purchased the car. Found a used one on eBay and replaced it. It worked. Just plug and play. The only thing is the vin # don't match. So I get an error in ista as well as an emergency call error on the dash. Not a big deal until I learn how to code the vin. Haven't really found out how yet.

After I posted above, removed the seat and somehow managed to get the module out by removing the plastic frame around it. I have no idea how I am going to reinstall it. During the process also managed to poke a hole in the under-the-seat harman kardon speaker with the spike that aligns the rear of seat to the frame l. FML.
However, this time around I couldn't get ISTA to read the buttons pressed on the switch.
Anyway, I ordered a used module with a part number which shows as bilaterally exchangeable in realoem. Hopefully that does it.

I could have tried the passenger side module, since they are the same. But after poking the hole on the speaker and realizing that I can't fit in the passenger side of the car in the garage, I just didn't have enough enthusiasm to put everything together, drive the car to center of the garage and do the whole thing again.

[trjn]

Update:
Part numbers:
In my car: 61359369125 (which is no where to be found in realoem or google. real oem has 61359369126
Ordered: 61359291508 (labelled as bilaterally exchangeable in realoem with 61359369126)


Installed the used seat module I ordered from an F01 with exact specs (comfort, heated seats) which showed as bilaterally exchangeable in realoem.
Seats buttons work, BUT, I get the driver's restraint system warning.

issues:
1. ISTA says the device is not coded for the car and not able to communicate with memory buttons?
- I thought the seat modules were not needed to be coded? How do I even code them to the car if they are? My car has the exact same seat system as the donor car.
- memory buttons work. Strangely, I think memory is stored in the module, as pressing the memory buttons brings the seats to a different settings(probably the ones stored in the donor car).

2. driver's restraint system
- There is not much in ISTA about it other than something about the power to the unit.

Probably the used unit I has the bad restraint system module within it? or coding it to the car will resolve the issue?(if possible). Going to see if I can install Esys in my system to get to code it.

At least now I know its the module and not the buttons or wiring.

TLDR:
installed a used seat module from F01, the buttons work but get driver's restraint system error.
put the original seat module back, driver's restraint system error goes away.

Bad module? or has to be coded to the car?

[trjn]

Returned the unit from F01 and got a unit from 2015 F10 535i(same year as mine). Part number is bilaterally exchangeable according to realoem.
This time results were different, none of the buttons worked and driver's restraint system fault was activated. Also this time there was no error about the module not being coded to the car. Installing the original one from my car, driver's restraint system error goes away.

I am pretty sure now that the unit needs to be coded to the car. Because according to realoem the module is same whether the car has standard, msports, comfort, active ventilation or massage seats. Probably the first unit since it came from F01 already had comfort seats, so the buttons worked but it car recognized it as not from F10 and set a 'needs to be coded' error. The latest one I got from F10 might not have comfort seats so the buttons are not working, but since it's from the same chassis style, it didn't need to be coded?

I am not really familiar with esys so, trying to see if anyone who has retrofitted the seats have some insight on coding the unit to the car.
My thought process is to code the car to make it think doesn't have comfort seats and revert back to comfort seats code. May be this would code the module to the car? Anyone have any suggestions on how to achieve that in esys?

But what about the driver restraint system error? Could it be a coincidence that both seat control units gave driver's restraint system error?

I am almost at a point where I might go to the dealership. Changed the switch block twice, changed the module twice, it's not the wiring. I don't have a problem buying a new unit(about $300), but I would just not want to pay dealership fees if it's simple enough to code the unit to the car.

[azzzor]

trjn Have you solved your problem? I bouth 535d 2014 with comfort seats and have same problem

[Hoa]

Check to see if the seat is getting power. If it does, your seat module is most likely the problem. If it doesn't have power then it's either a fuse or a damaged wire somewhere between the fuse box and seat

[M_Bimmer]

Originally Posted by trjn

OLD POST

This is an old post, but just incase others are interested.

Almost everything OP posted is expected when dealing with seat modules.

Going back to 1st post, I'd ask for the real codes being thrown by the seat module. If past that point, then I'd recommend recoding the original module......

When you get used modules, it must have the same I-STEP, else you will have issues and and F01 vs F10 do not have the same I-STEP...and when trying to VO code, you may achieve partial success. Also, original seat modules from the factory are numerous and widely varied on what electronics are populated on the circuit card. Realoem doesn't always have all part numbers that are interchangeable, and the new units you can buy, are limited on variations to reduce supply chain burden on BMW.

BTW, depending on F10, year and options, the seat sensor that supports the SRS system are different...and there are two variants and they are not interchangeable, w/o changing out the seat sensor. This will set the seat SRS dash light.

[Hoa]

I-Step and production date matters a lot. I swapped a seat in my car and ran into those issues. Both were from 2014 5 series but production date for the donor vehicle was late 2013 while mine was early 2014. I could not figure out why my original module would not throw an airbag light while donor module would. VO code my original module to match the new seats didn't work. I eventually updated the I-Step on the donor module and airbag light disappears immediately.

[trjn]

Originally Posted by azzzor

trjn Have you solved your problem? I bouth 535d 2014 with comfort seats and have same problem

Yes. It was the module that was bad. Finally I ordered one from 2013 550i which had the same seats (comfort, heat, memory, no ventilation or massage). Hardware was plug and play. And once I coded the module to my car via esys, the airbag light went away.

[Arthuar]

I got seat issue either.
Bmw F10 comfort seat ventilated.Passenger front seat is working full...almost.
The small cushion, under the knee, doesn’t work, no movement at all.
I hear the small engine running, when I move the button, though the cushion is stuck.
I don’t think it’s an electric issue.No fault code found.

What do you think it could be...

[M_Bimmer]

Originally Posted by Arthuar

I got seat issue either.
Bmw F10 comfort seat ventilated.Passenger front seat is working full...almost.
The small cushion, under the knee, doesn’t work, no movement at all.
I hear the small engine running, when I move the button, though the cushion is stuck.
I don’t think it’s an electric issue.No fault code found.

What do you think it could be...

https://www.youtube.com/watch?v=xzCEpXqauXQ

[Arthuar]

Originally Posted by M_Bimmer

https://www.youtube.com/watch?v=xzCEpXqauXQ

Thanks, late.
Yes you are right, now I must find the spare piece on eBay.

[M_Bimmer]

Originally Posted by Arthuar

.....now I must find the spare piece on eBay.

You Mean This Part?

[ex46fanatic]

Originally Posted by trjn

Yes. It was the module that was bad. Finally I ordered one from 2013 550i which had the same seats (comfort, heat, memory, no ventilation or massage). Hardware was plug and play. And once I coded the module to my car via esys, the airbag light went away.

Hey bro please hear me out with my problem. F06 640i GC, i retrofitted comfort seats (just needed power to pin 1), all was well until a thin drinks can popped under my seat squirting liquid out slowly - i later take the seat out to clean, reinstall,and then i lose power movement to my passenger seat - but heating and lumbar works.

Ista said its a problem with the lin bus in the seat. So i replaced the seat wiring loom (£200)... problem still the same. Before this i had swapped switch blocks and modules with the driver side, same problem exists.

Any ideas at all?! Ive visually checked fuses but not with a multi meter, they appeared intact.

[ex46fanatic]

Please have a look at my problem above. Been stuck for over a year now.

Originally Posted by M_Bimmer

This is an old post, but just incase others are interested.

Almost everything OP posted is expected when dealing with seat modules.

Going back to 1st post, I'd ask for the real codes being thrown by the seat module. If past that point, then I'd recommend recoding the original module......

When you get used modules, it must have the same I-STEP, else you will have issues and and F01 vs F10 do not have the same I-STEP...and when trying to VO code, you may achieve partial success. Also, original seat modules from the factory are numerous and widely varied on what electronics are populated on the circuit card. Realoem doesn't always have all part numbers that are interchangeable, and the new units you can buy, are limited on variations to reduce supply chain burden on BMW.

BTW, depending on F10, year and options, the seat sensor that supports the SRS system are different...and there are two variants and they are not interchangeable, w/o changing out the seat sensor. This will set the seat SRS dash light.

[M_Bimmer]

Originally Posted by ex46fanatic

Please have a look at my problem above. Been stuck for over a year now.

The seat assembly swith assembly (S32) is connected to your seat electronics, SMFA (A93), on the Driver's seat.

If this were my car, I'd make sure that the S32 was free of "soda" and verified that the seat harness is engaged in the S32 assembly correctly.

If you are OK with swapping your SMFA with SMBF, and if your LIN bus error moves with the seat module, then you have an issue with your SFMA module.

[ex46fanatic]

Originally Posted by M_Bimmer

The seat assembly swith assembly (S32) is connected to your seat electronics, SMFA (A93), on the Driver's seat.

If this were my car, I'd make sure that the S32 was free of "soda" and verified that the seat harness is engaged in the S32 assembly correctly.

If you are OK with swapping your SMFA with SMBF, and if your LIN bus error moves with the seat module, then you have an issue with your SFMA module.

Sorry I did not explain the issue properly... The drinks can made the mess under the passenger seat and the passenger seat is affected. Nothing happened under my driver's seat. Problem is all with passenger. Do your comments above still apply?

I tried about a year ago by swapping seat switch blocks and modules to try to test, this made no change, but I will try again now I have new passenger seat wiring installed.

Biggest annoyance has been for everyone who sits in the unadjustable passenger seat tilted a bit too forward.

Really appreciate your appearance here.

[M_Bimmer]

ex46fanatic , same applies....

If you don't make any progress, I'd recommend that you'd consider using ISTA+ test plan. Pull your ISTA+ BMW error codes, then run the "test plan" corresponding to your seat LIN error only. It should eventually require you to run your seat calibration, and if your seat still can't move, I'd look at getting a new seat switch block off of Ebay...but get the right one. Pre-LCI is not the same as LCI seats.

Keep posting your progress.

Cheers.

[ex46fanatic]

Originally Posted by M_Bimmer

ex46fanatic , same applies....

If you don't make any progress, I'd recommend that you'd consider using ISTA+ test plan. Pull your ISTA+ BME error codes, then run the "test plan" corresponding to your seat LIN error only. It should eventually require you to run your seat calibration, and if your seat still can't move, I'd look at getting a new seat switch block off of Ebay...but get the right one. Pre-LCI is not the same as LCI seats.

Keep posting your progress.

Cheers.

You're definitely onto something. I've just pulled up below codes from ista after having the new passenger seat wiring installed for about 2 weeks now. (Been busy).

I will investigate the below as soon as I can. ECU code is for stage 1 remap. For the Ewg code I have new ewg ready to install, again just been busy and the code is intermittent.

Backrest lock switch codes are on both driver and passenger fyi, but currently not present.

I'm not sure I need to swap modules, but it does look like a new passenger seat switch block is needed. I will run test plan when I get time.

[Barry.Ib]

Hello Guys
I have an issue with the power seat driverside on my 535i Xdrive(f10/2014)it stopped working right !It started with an abnormal Sqeaky 💤 Noise while moving the seat forward and Backward and I didn't like the noise it was causing.So I sprayed WD-40 on both side of seat below now it got worst !the seat doesn't move neither forward or backward,the left side of the seat facing the driver door side moves a bit but twists toward the right side !When I look below the seat I saw a crack on plastic robber under the seat and I feel like the right side motor not working right too. I really want to fix it but has no clew where to take my car !I don't intend to take it to BMW dealer the overcharge !Am looking for shops that repairs power seat does anyone know any around Philadelphia,New Jersey or New York. I would really appreciate any Recommendations Thanks guys

[ex46fanatic]

Finally got new switch block for the problem passenger seat on the way (£130 used off ebay)- i cannot control the seat from ista. Lets see what happens.

Originally Posted by M_Bimmer

ex46fanatic , same applies....

If you don't make any progress, I'd recommend that you'd consider using ISTA+ test plan. Pull your ISTA+ BMW error codes, then run the "test plan" corresponding to your seat LIN error only. It should eventually require you to run your seat calibration, and if your seat still can't move, I'd look at getting a new seat switch block off of Ebay...but get the right one. Pre-LCI is not the same as LCI seats.

Keep posting your progress.

Cheers.