Re-upholstering Recaro Sportster CS in Fox Red with heating.

[6ixSpd]

Full write-up is linked on my blog here:
https://6ixspeed.com/2020/05/13/custom-recaro-cs/

Finally got these bad boys installed!

Huge shoutout to AMX Performance (https://amx-performance.com) aka Recaro Max for supplying the covers in early 2019. The workmanship is fantastic, with perfect seams and 100% original quality leather. The covers come with the original Recaro attachments for a complete factory swap without the use of hog rings or any custom work. Shipping from Poland was very quick and the parcel was carefully packaged. He even offered some customer support for the questions I had going along with the DIY process despite having no obligation to do so. I cannot praise AMX’s products enough.

I also bought aftermarket heating elements in a quest to integrate them with factory center console heating controls. Nowadays AMX sells the OEM BMW heating elements for a complete PnP solution with factory controls.

Parts Required

• Various small flat head screwdrivers and picks
• various sockets, wrenches, and torx bits (to remove stock seat belt receptacle assembly) depending on your mounting hardware
• set of seat heating elements
• wire stripper & scissors
• electrical tape
• cloth wrapping tape
• soldering kit

What I Did

I removed the stock black covers on the Sportster CS seats and replaced with AMX supplied covers. I went with OEM Fox Red hide, embossed ///M logo in the headrest, and a ///M tricolor motif in a nod to the E36 M3 Vader seats I always lusted for back in my E36 days.

• Started by peeling back the sealing gaskets from the headrest and worked my way down:
  
  
  
• Installed aftermarket seat heating elements on the seat cushion and backrest foams.
  
  
  
• Painted the cutout surrounds in a metallic satin silver:
  
  
  
• All re-upholstered and buttoned up ready for wiring. You can see the creases and wrinkles needing to be tightened up with a heat gun (explained below):
  
  
  
• Wired the cushion and backrest elements directly to the stock E92 underseat power and ground sources with the original BMW connections and plugs.
  
  
• Luckily, the original Sportster seat frames already have provisions for installing a heating switch.
  
  
• Installed the stock seat belt tensioner and connected it to the car’s stock wiring and coded out a few items.
  
  
  
• Used OEM wire management attachments which and factory cloth tape, I cleaned up my wiring to be as original looking and out of the way as possible. OE plugs/connectors were used for a full plug and play and 100% reversible solution.
  
  
  
• All the wrinkles and creases in the leather hide from being stored for a year in my basement were an eyesore. A heat gun is what the professionals use to really smooth out leather to like-new condition. The trick was to keep the gun moving at a constant pace while applying heat to the desired area. This worked wonders as 99% of the wrinkles/creases are GONE and a uniformly smooth, tight fitting leather remains.
  
  
  
  
  
• Swapped in a non-heated seat climate control panel to clean up the redundant buttons.
  
  

End Result

No errors, no warnings, heating works great and the seat belt butlers still deliver the belts.
I noticed a drop of approx. 2” from the factory seats. The entire assembly with the Sportsters, heating elements, wiring, sliders, Planted floor mounts, and seat belt tensioner weighs 48 lbs. The entire factory seat assembly including all controls and tensioner weighs 65 lbs, for a weight savings of 17 lbs/side. Not bad!

Notable Items

• If I had to do it again, I would likely go with BK mounts with OE sliders. The Planted Technology mounts are okay for use with these seats and do a good job with ease of installation and still drop the seat height appreciably, but they're not without issues. The bracket for the seat belt receptacle interferes with full fore/aft motion of the slider’s range. Though it doesn’t make any difference because I can’t imagine anyone would sit further up to the wheel than the limit this allows anyways.
  
• The floor mounting hole positioning of the Planted mounts is at the extreme limit of clearing the floor board of the car. The bolts barely cleared to line up and thread straight. Stock bolts CANNOT be re-used here as their height will not clear the available vertical space between the floor and the plate to which the sliders are secured. M10x1.5 25-30mm bolts are needed.
  
• Coding: ensure all of the following are set to nicht_aktiv in ABG module:
  SIDEBAG_LINKS_1 -side airbag (left)
  SIDEBAG_RECHTS_1 - side airbag (right)
  AKS_LINKS_1_CD - active head restraint (left, for 2009+ cars)
  AKS_RECHTS_1_CD - active head restraint (right, for 2009+ cars)
  OC3_1 - passenger seat occupancy mat 1/2
  GK/OC3/POL - related to the passenger occupancy mat 2/2
  SPSF_1_CD - seat position sensor (driver)
  SPSBF_1 - seat position sensor (passenger)
  
  Clear all errors in the ABG module via Tool32 > MRS5.PRG -> execute fs_loschen job

The Original Plan

Initially I wanted to use the aftermarket elements with factory controls for 100% OEM integration. I wired in a NTC thermistor into the cushion element’s connection as per TIS’ schematics and used OEM connectors to plug into the smaller/base underseat module. This would not work properly, and the circuit would shut off after about 3 minutes.

The reason being the thermistor I was using was not enough with the resistance values of the aftermarket elements compared to the stock setup. The power differentials were not within range of the stock PWM modulations.

Trying to reverse engineer this with aftermarket elements and a calculated NTC thermistor value is beyond my scope of understanding, and ultimately not worth the trouble. If I had to do it again, I would simply buy the OEM elements from AMX. Unfortunately in my case, by the time I had assembled the covers with the heating elements in summer 2019 there was no factory solution being offered until just a few months ago in 2020… C’est la vie.

[M3ANMACHINE]

Very nice! I documented my DIY of the covers I got from AMX as well in my build thread!
https://www.m3post.com/forums/showpo...&postcount=110

Definitely top notch quality and the price is well worth it. Stock seats gave me major back pain. Being in SoCal heated seats weren't really necessary but very cool that you added them to your setup! I still need to heat gun a couple wrinkles from mine.

In regards to the BK mounts with OE sliders, they don't drop the seat height at all which is the main reason I opted for different mounts.

Enjoy em in good health!

[Marek AMX]

Congratulations!!!
Well done!

[m3_tristan]

Awesome write up! Glad we found ways to use the oem searing wiring to power these bad boys

[//steve\\]

These look absolutely amazing! Wrinkles in nice new leather covers are often the one thing that tends to make what should be nice replacements look terribly cheap. I'm glad to see the quality looks spot on to OE or better. And I love the tri-stitch color touch on the seat back.

[Redd]

Nice! I think white with fox red interior is the best combo from factory!

[derbo]

Kudos!

I will most likely buy the airbag/heat set from AMX in the end.. :X

[wyatth]

Absolutely stunning!

[JPWEraser]

Well done sir. These are excellent.

[6ixSpd]

Thanks gents!

Originally Posted by M3ANMACHINE

Very nice! I documented my DIY of the covers I got from AMX as well in my build thread!
https://www.m3post.com/forums/showpo...&postcount=110

Definitely top notch quality and the price is well worth it. Stock seats gave me major back pain. Being in SoCal heated seats weren't really necessary but very cool that you added them to your setup! I still need to heat gun a couple wrinkles from mine.

In regards to the BK mounts with OE sliders, they don't drop the seat height at all which is the main reason I opted for different mounts.

Enjoy em in good health!

The heat gun makes ALL the difference. I wasn't thrilled with some of the wrinkles I incurred from letting the leather sit in their shipping box for so long, and the steamer did nothing. Once I hit all the loser areas with the heat gun I was absolutely in love with how perfect they turned out.

And shame to hear the BK mounts would negate most of the benefits of dropping the seat height I guess Planted remain the best ones so far from that aspect.

Originally Posted by m3_tristan

Awesome write up! Glad we found ways to use the oem searing wiring to power these bad boys

Originally Posted by //steve\\

These look absolutely amazing! Wrinkles in nice new leather covers are often the one thing that tends to make what should be nice replacements look terribly cheap. I'm glad to see the quality looks spot on to OE or better. And I love the tri-stitch color touch on the seat back.

I agree 100%, once the wrinkles were worked out these looked 100% worth every penny.

[Webb70]

Damn, they look amazing.....great job !

[acarr6]

Now this is a write up!

[nm]

Very nice

[Richbot]

Damn

[Bpark1977]

I would 100% rock those sweet sweet seats, if I didn't have a vert.

Very nice work.

[91foxbody]

Those are rad, I need to pin this for when I get the itch to replace mine.

[aajami]

Originally Posted by 6ixSpd

[*]Coding: ensure all of the following are set to nicht_aktiv in ABG module:

Thanks for the detailed writeup. Since you've coded out the following elements...

SIDEBAG_LINKS_1 -side airbag (left)
SIDEBAG_RECHTS_1 - side airbag (right)
OC3_1 - passenger seat occupancy mat 1/2
GK/OC3/POL - related to the passenger occupancy mat 2/2

Does that mean that neither the side airbags nor the passenger airbag will work in an event of a crash where they'd ordinarily deploy?

Also, what does the seat position sensor do?

SPSF_1_CD - seat position sensor (driver)
SPSBF_1 - seat position sensor (passenger)

[M3ANMACHINE]

Originally Posted by aajami

Thanks for the detailed writeup. Since you've coded out the following elements...



Does that mean that neither the side airbags nor the passenger airbag will work in an event of a crash where they'd ordinarily deploy?

Also, what does the seat position sensor do?

If coded properly, they should theoretically deploy regardless of an occupant being in the passenger seat as opposed to On or Off depending on if someone is sitting in the passenger side.

[6ixSpd]

Originally Posted by aajami

Thanks for the detailed writeup. Since you've coded out the following elements...
Does that mean that neither the side airbags nor the passenger airbag will work in an event of a crash where they'd ordinarily deploy?

Also, what does the seat position sensor do?

Euro spec BMWs did not have OC3 mats. In North American cars, OC3 is meant to not deploy the passenger front airbag if it detects an occupant weighing less than 40 lbs., i.e. a child. Coding it off sets it to deploy in a crash regardless if the seat is occupied or not.

The side airbags in the doors are untouched. It's the ones in the seat bolsters that are coded off because most aftermarket seats do not have them and thus trigger SRS errors.

Originally Posted by M3ANMACHINE

If coded properly, they should theoretically deploy regardless of an occupant being in the passenger seat as opposed to On or Off depending on if someone is sitting in the passenger side.

Correct

[aajami]

Originally Posted by 6ixSpd

Euro spec BMWs did not have OC3 mats. In North American cars, OC3 is meant to not deploy the passenger front airbag if it detects an occupant weighing less than 40 lbs., i.e. a child. Coding it off sets it to deploy in a crash regardless if the seat is occupied or not.

The side airbags in the doors are untouched. It's the ones in the seat bolsters that are coded off because most aftermarket seats do not have them and thus trigger SRS errors.


Correct

Thanks for the clarification. Don't the OEM seats have airbags in them? Doesn't that mean that, by going with these Sportsters and coding out their airbags, that you're reducing the number of airbags that can deploy in certain situations?

[derbo]

Originally Posted by aajami

Thanks for the clarification. Don't the OEM seats have airbags in them? Doesn't that mean that, by going with these Sportsters and coding out their airbags, that you're reducing the number of airbags that can deploy in certain situations?

That is correct.

BMW performance ones have seat airbags and Recaro sells a Sportster with airbags but outside of North America. AMX does sell a solution that retains the airbags and plug n play. You will still need to code out the OC3 mat since they don't have it (or hack a stock seat for it to retrofit).

[GRUESOM3]

Subscribed. Thanks for the write up. I hope mine come out with no wrinkles.