[Ivegotissues666]

Alright it's finally put to rest Heated Seat Retrofit. So here goes my DIY with lots of pictures documenting my process, materials/tools used and needed.

Parts Needed:

1. Heat Seat Elements Baffles - I purchased for $100 from a fellow fanatic
2. Heated Seat Accessory Panel with the Heated Seat buttons - I got lucky on this one of ebay (I got the sunglasses console climate control version with the climate control unit, the accessory panel, and ashtray for ~ $80
3. Wiring, Fuses, Butt-Connectors/Quick disconnects, Zip Ties and various OEM BMW specfic connectors/pinouts - Already had so $0 for me!
4. An Upholstry Shop capable of doing car seats, I found one 5 minutes from me and charged me $150 per seat - $300 total

So my total cost was ~ $480

Here are some pictures:

Tools Needed:

Torque Wrench
T-15 Socket
T-40 Socket
T-45 Socket
10MM hex socket
17MM hex socket
Philips Head Screwdriver
FlatHead
Needle Nose Pliers
Crimping Tool

Allright lets get started:

Step 1: Disconnect your battery

Step 2: Remove/Unplug your seats from the car

Step 3: Once the seats are removed, nows the fun part! Dismantling your non-heated seat baffles. It's actually fairly easy start by taking off the backrest portion this is only held on by 2 T-40 bolts you must pull back the leather/leatherette to gain access to them. Once these 2 bolts are removed the backrest will come free with a little bt of strength.

 

[Ivegotissues666]

Flip the seat upside down and you will notice I think they are called HOG RINGS. Well you can use a pair of pliers to undo the ring there are 2 - 3 on each side left nright at the back of the seat.

Now you have to remove these other 2 T-15 bolts attached to these plastic covering. This will give you access to pull off the bottom seat baffle. It is held on by a long plastic molding/clip and can be easily popped up with either your fingers or a flathead screwdriver. Just work your way pulling up that molding and you will eventally hve the bottom part of your seat free. (Note: On the passenger side bottom protin of the seat, there is a sensor that has to do with the airbag. It is part of the seat and shld be dealt with delicately.)

Step 4: Take your non-heated seat baffles to an upholstry shop and have them put the heated elements into them. In the meantime let's work on your wiring harness considering you wo't be able to drive with no seats. haha

Step 5: I opted not to puchase the OEM BMW retofit kit simple because I wanted a challenge first off, and second I wasn't going to pay ~ $300 for a wiring harness and button panel that I could easily make and obtain. First lets look at Heated Seat Retrofit PDF manual, it gives detailed information on the wirig harness. I read through i and simplified what the harness is all about here is the way I saw it as:

To Passenger seat Side:

B1 - Seat Heating On (GN/YE) - Plug X279 Pin 25
B2 - Ground (BR) - Plug X279 Pin 24
B3 - Temperature (WT/BL) - Plug X279 Pin 23
B4 - Ground (BR) - Under Pass Side Skirt (B2 <---> B4)

To Driver seat Side:

A1 - Seat Heating On (GN/VI) - Plug X275 Pin 25
A2 - Ground (BR) - Plug X275 Pin 24
A3 - Temperature (WT/GN) - Plug X275 Pin 23
A4 - Ground (BR) - Under Driver Side Skirt (A2 <---> A4)

To Console Switch:

Passenger Side:

B1.1 - Seat Heating On (GN/YE) - X1869 Pin 1 (B1 <---> B1.1)
B3.1 - Temperature (WT/BL) - X1869 Pin 20 (B3 <---> B3.1)

Driver Side:

A1.1 - Seat Heating On (GN/VI) - X1869 Pin 13 (A1 <---> A1.1)
A3.1 - Temperature (WT/GN) - X1869 Pin 21 (A3 <---> A3.1)

To Fuse Panel:

C - K-bus (WT/RD/YE) Fuse Box Joint Connector X10116 (Trigger/Accessory Wire) Pin 23 - Console Switch
D - Terminal 30 (RD/VI) Fuse Holder A46 slot No. F42 (30 amp) Pin 7 - Console Switch
E - Terminal R (VI/BL) Fuse Holder A47 slot No. F12 (7.5 amp) Pin 22 - on Console Switch

As you can see I simpilfied it or at least to me it seems that way. Anyways lets start wiring.

Step 6: Removing Glove Box and Driver side steering column panel, both are held in by philips head screws. Now lets start making your wiring harness. Starting with the drivers side you need 3 wires (1 for Ground, 1 for Temperature, and 1 for Power (Heating On function) I didnt have the multicolored wires like BMW so I just made do with what I had. I tried to match the wire colors up as best I could for instance if the OEM wire was White/Green I would make my wire White etc..

Drivers Side:

16 Gauge wire: (The Green Wire should have been 14 Guage but I didn't have any available and the 16 Gauge should be fine)

White - 9 ft (Temperature Wire) - Pin 23 at the Drivers Seat Plug
Green - 9 ft (Heating On Wire) - Pin 25 at the Drivers Seat Plug

Brown - 3 ft (Ground Wire) - Pin 24 at the Drivers Seat Plug

 

[Ivegotissues666]

I routed the wires under the foot trims and behind the steering column panel to the consle area where the accessory panel with the heated seat buttons will be located. The Ground wire is connected in a Stock Grounding point underneath the carpet. You need to pull the carpet up a little bit in order to access it and there are a few empty slots (Note: You will need a OEM pin connector to get it to secure correctly you will need to crimp or solder this connector to the Brown wire in order to supply a Ground connection to the seat)

Passengers Side:

It is the same method as the Drivers side in terms of routing the wires. The Grounding point will be bend the carpet, and youwill rute the wires behind the fuse panel to the console area where the heated seat buttons are located. The wire colors I used for the Passenger side are:

Blue - 9 ft (Temperature Wire) - Pin 23 at the Passengers Seat Plug
Yellow - 9 ft (Heating On Wire) - Pin 25 at the Passengers Seat Plug

Brown - 3 ft (Ground Wire) - Pin 24 at the Passengers Seat Plug

Fuse Panel:

The fuse panel is suspended by 2 plastic knobs, you must open the fuse panel and then push the fuse panel up in order to release the panel from it's mounting points. Once this is accomplished the fuse panel will drop down and give you more room to access and play around with.

Now running wires into the fuse panel is a little tricky yet still doable. You will need an additional 3 wires plus some OEM BMW connectors:

1 - 12 Gauge Wire ~ 7 ft - Red (Run this wire from fuse #42 - 30 AMP Fuse to the center console area, this s what supplies most of your power to your heated seats

2 - 16 Gauge Wires ~ 7 ft each
- Red/Yellow (Run this wire from the comb connector that has all the Red/White/Yellow Wires on the fuse panel to the center console area. This is basically turn on Lead for the Heated Seats)

 

[Ivegotissues666]

- Blue (Run this wire from fuse #12 - 7.5 AMP Fuse to the center console area)

Step 7:

Now working at the center console area with the 23 pin plug connector. You just ran 7 wires to the console area. Those being:

1. White
2. Green
3. Blue
4. Yellow

5. Red
6. Red/Yellow
7. Blue

These connect to the 23 pin plug at the center console area in the following order. You must crimp or solder the connections and put them into the 23 pin plug connector.

1. White - Pin 21
2. Green - Pin 13
3. Blue - Pin 20
4. Yellow - Pin 1

5. Red - Pin 7
6. Red/Yellow - Pin 23
7. Blue - Pin 22

Note: There is also a little 3 pin connector on the backside of the accessory panel you can plug n your DSC (4 pin) connector to this the new panel uses one less wire which I think is 12v Constant because it is now being supplied from the fuse panel.

Step 8:

Now go back to other the Drivers and Passengers side harness that are found underneath the seats. You must unlock the connectors first. Once you have done this now locate on the:

Drivers Side: Pins 23-25 Crimp or solder the pinout connectors as follows:

Pin 23 - White
Pin 24 - Brown
Pin 25 - Green

 

[Ivegotissues666]

Passenger Side: Pins 23-25 Crimp or solder the pinout connectors as follows:

Pin 23 - Blue
Pin 24 - Brown
Pin 25 - Yellow

Now lastly resecure the connectors and you are done with the wiring portion.

Step 9:

Pick up your seats from the Upholstry shop if you don't have them already and begin to reassemble your seats. Installation is the reverse of removal only difference is that you must swap out the seat belts that come with the additional wiring for heated and power seats. Using your T-45 socket undo the seatbealt and trace the wiring undoing the plastic clips that secure the wiring harness and remove the old connector. Installation of the new seatbelt and wirng harness is the reverse of the process youjust used to remove the old one. Also there is a 2-3 pin male and female connector that connect both the backrest of the seat and the bottom part of the seat make sure it is connected or else the heating elements will not work.

 

[Ivegotissues666]

Step 10:

Once the seats are reassembled, put them back into your car and bolt them down torquing everything to spec. Plug in the 25 pin female plug connector under the seats to the new male wiring harness attached to the seats.

Now working at the center console area plug in the 23 pin plug connector to the back of the accessory panel and the also the 4 pin plug connector if applicable.

Step 11:

Reconnect your battery, and start your car. And.... there you have it, heated seats!!! Push the button once and all 3 lights on the button should light up. Push it a second time and only 2 will light up, this is part of the temperature setting to set at a certain temperature.

Once Everything is working correctly reinstall everything (Foot Sills, Covers, GolveBox everything is reverse of removal) Just a quick note: the wire colors I used are for my reference only because those are the colors I chose to use they are not the BMW OEM Wire colors as found in the retrofit PDF file. Also if anyone wants the retrofit pdf file just PM me with your email and I will gladly send it to you, unless someone would be kind enough to host it for me and everyone on the forum.

Well I have to say this retrofit wasn't as bad as I thought it would be. I'd say it took me 6 hours total from running the wiring neatly to reassembling the seats, besides the couple days of downtime of waiting for my seats at the Upholstry shop. I never ran into any issues with wiring snce I've wired my (Foglights, Angel Eyes, and Footwell Lightng, Heated Steering Wheel) driecty from the fuse panel so I really didn't expect to have an issue with this.

I hope this write up comes in handy for those who want to attempt this or are in the process of doing it. I so far after only one day of having heated seats hae not one regret about doing this retrofit and yet the heated seats compliment my Heated Steerng wheel as well.

My next mod/retrofit I'm looking into I think would be did you hear Heated Rear Seats!! Just from looking at the heated elements and the looking at my rear seats I know it is possible and would be easier than the fronts haha!!! I knw it would work for sedans, but I'm am ot so sure about the coupes.

And just clarify things there really is no weight difference noticable at least between regular manual seats and heated seats. They both weigh roughly the same still pretty heavy if you ask me. It's when someone with Heated/Power seats comes into play now those suckers are heavy.

Any comments/questions feel free to contact me and even if your in my area and want to do this retrofit I would be willing to lend you a hand.

Anyways Enjoy!! :evil:

Jared

 

[LAFENGAS]

Looks good Jared. Looks a lot more labor intensive then you would think. So what's next? Power seats?

DIY's ROCK!

 

[Ivegotissues666]

Looks good Jared. Looks a lot more labor intensive then you would think. So what's next? Power seats?

DIY's ROCK!

Thanks, yeah I'm all about DIYS and yes Power seats next and then..... I think I might give it a try on heated rear seats but who knows.

I saw your post about about covering your seats now in suede was it? How did you go about the upholstry? Yourself or a Shop? If your doing it yourself I thought you needed like a special machine other than a regulare sewing machine?

Jared

 

[LAFENGAS]

..... I think I might give it a try on heated rear seats but who knows.


Jared

That's what i'll likely be doing, rear heated seats.


I'm using Alcantara, which doesn't require a special machine. I haven't decided if i'm going to do it myself or leave it to a shop.

 

[xmltok]

How much did the alcantara run you? The leather on my front seats is looking a little worn, alcantara front and back would be sick!

 

[Ivegotissues666]

What?! 138 views and no one cares to comment or thank (except one person :thumbup: by the way) for providing a DIY that I took the time to write up for fellow fanatics. Did everyone just add the page to there favorite and were done with it. Now I'm not even sure I will provide everyone with a Retrofit DIY of Non-Power - Power seats once I get the seat frames in. I mean that is if no one seems to appreciate the time people invest into a project to share with the community.

Anyways //end rant!

 

[Asterisk*]

Blah.

I commented.

Chill man. Not everyone has enough balls to do stuff like that. More then a half already have heated seats. Some just don't want to do it, the others don't have money for it. So we are rougly come to about me, you and that one guy to appreciate the DIY opportunity. Good write-up nevertheless.

 

[Ivegotissues666]

Not everyone has enough balls to do stuff like that. More then a half already have heated seats. Some just don't want to do it, the others don't have money for it. So we are rougly come to about me, you and that one guy to appreciate the DIY opportunity.

It has nothing to do with wether someone is capable about doing this or being able to afford it. What mainly pisses me off is the fact that someone will post another 1 millionth angel/DDE thread NOT even a DIY and yet still manage to get 50 comments, feedback etc.. Honestly how would you have felt when posting your dying of your seats and not received a single comment for taking your time to document your process w/pictures etc..

Good write-up nevertheless.

See this is exactly the kind of feedback I was looking for, Thank you! Also your seats look :drool: I wish I was into the 2-tone look in my car

 

[Bavarian46]

I ever so often check the DIY section, hoping to fine something new and exciting. Once in a while a good fanatic brings worthy DIY to the menu. A definite must have for the fanatics living in the colder climates. Thank you and good luck with future DIY’s. :thumbup:



.

 

[kneb]

Thank you very much for posting this. I'm sure you put a lot of effort in to this writeup, and it is very much appreciated (at least by me).

 

[LAFENGAS]

I'll be refering to this DIY when I attempt to do my rear seats. That's a lot of information on the wiring... where'd you find it?

 

[Pigeon]

Nice job. Just a few comments:

When I swapped in my M3 seats I pulled the entire seat with rails out, just unbolt the one bolt that holds the seat belt end to the outboard rail - that way you don't have to disassemble the rail in the car as I noticed you did.

The seat belt tensioners (the buckle end of the belt) don't have to be changed. Just disassemble the yellow underseat connector attached to the seat by pulling off the black cover (slides off one way) and then the individual plugs for the seat belt tensioner circuit, power adjustments and heating can be removed from the "master" plug and swapped out as needed. I had to do this with my M3 seats as well since the new tensioners had different wiring so I had to reinstall the old ones to keep the airbag computer happy. BTW, that tensioner is an explosive, be careful with it.

Enjoy your warm seats!

Scott

 

[sli]

I want heated seats!

Fantastic writeup!!! I am in awe of your ingenuity. I've been poking around trying to find out if it can be done. FANTASTIC! When I bought my car, they had one coming in with everything I wanted but heated seats. I was told it could be done later - no way from the dealer. Where can I get the Heat Seat Elements Baffles? I called a BMW recyler he had no idea what I was talking about - though I was asking for the heated seats element. I wonder it RealOEM.com has the part? Any help on where to get the other parts? THANK YOU!!!!

 

[Asterisk*]

Honestly how would you have felt when posting your dying of your seats and not received a single comment for taking your time to document your process w/pictures etc..

See this is exactly the kind of feedback I was looking for, Thank you! Also your seats look :drool: I wish I was into the 2-tone look in my car

Frankly, I would feel like "F U ALL I'm not posting any DIYs or tips and tricks for this and that anymore". :thanks:

Thanx for a compliment on the seats! Made my day.
I wish I had your :nerd: knowledge about electrical stuff in our cars. :bow: Probably I just need to start to mess with it (never did it at all).

I'm gonna be throwing in powered&heated seats in my manual seats car. I've noticed there is already some kinda harness with plug underneath the seat. Hopefully it's gonna be plug&play, but I'm concerned about wiring the seat heater buttons. I have a wrecked car with a premium package so I'll be getting all the parts out of it and just have that little concern if nothing's gonna work out. You know - never tried to mess with electrical stuff. Don't even know where the fuze box is located. lol. Though I heard there is 2 of them. I'll be hoping your thread will help me to achieve the desired results.

 

[10bmw10]

nice writeup, if someone ends up doing one for the rears that would be awesome! I wish they came in the rear seats also

I totally understand how you felt on no comments, i made an old write up on an alternator change but nobody really cared so i said **** it im not gonna post anymore diys.

great job!

Brian