[sleepyonthehighway]

Hey all, first post b/c this is the first major problem I've had with my Z4.

I have a 2007 Z4 E85 3.0i that came with the standard pleather seats, motorized but NOT heated.

Driver's seat was falling apart, so I was going to replace anyway, but I got a pair of heated seats off eBay to add this functionality. I got the control module too, so that I could turn the seats on and off.

Seats came in, installed everything, all connections are good, but the seats don't work. I have power to the seats, because I can move them, but when I try to activate the heat the light blinks green very quickly then goes away, for both seats.

I asked one of my friends who works at a BMW dealership what could be wrong, and he told me the module needed to be programmed, but that he couldn't do it so I had to bring it in. This was the first trip I've had to make to the dealer.

Just got the call that the dealer couldn't figure it out either. They programmed all the modules, but the seats still do not work. Service advisor said "There appears to be some unplugged connections." So I spent $300 for nothing.

Worth noting these seats are from a 2003-2005 pre-facelift Z4, as evidenced by the 2-pin passenger occupancy sensor, but aside from that one plug on the passenger side all other plugs are good. I have an airbag light on b/c of the occupancy sensor, but the delete should be here in a few days.

What am I missing here? Since my car is apparently not pre-wired for a heated seat option (I would have thought it would be), what connections do I need to make?

I am hoping for a savior here, I have scoured the forums and seen a few dead posts about things similar to this. If you have any idea, please please let me know. I have put so much work into restoring this Z and this is a huge roadblock for me.

Much appreciated,
Sleepy

 

[sleepyonthehighway]

Since I am doing lots of research on my own, I am hoping to turn this into a retrofit guide for those who are in the same boat as I am. I had a long conversation with the former service manager at the dealership (think he's in sales now) and he recommended a few things for me to do:

First, he told me to abandon the project and put aftermarket heater-pads on, and tie in a switch, call it a day. NEVER.

He then told me he also believes my car is pre-wired to support factory seats. So, unlike many other retrofit guides, I shouldn't have to add any lines to the JBE or VO or whatever. This is because I already had power seats, just not heated seats. If your ride has manual seats, I've read enough forums to know that you will need to handwire seats. this diagram may be useful to you, makes no sense to me:

http://imgur.com/7CBw9qm

http://imgur.com/LFHloiI

source page: Heated seats retrofit (now complete) - babybmw.net



Second, he told me to look into coding the VO myself. I am very new to this side of BMW maintenance, so if you're also new, don't worry. VO is Vehicle Order:
For the uninitiated, this is a string of alpha-numeric codes reflect exactly with which options that car left the factory.
(source: Understanding BMW's ZCS System — Bimmer Coding NA)

Most importantly here, in the VO, is the specific alpha-numeric code for the heated seat option, which is S494, also seen as $494.

I am still trying to find the exact module which this will be under. But I'm getting ahead of myself for the others that may come upon this thread and be as lost as I was before hours of research.

First step is to go to bimmergeeks and get the free software:

Downloads

Find K+DCAN & Enet Cables and the Bmw Software you need all in one place.

www.bimmergeeks.net

I downloaded the "Bimmergeeks Standard Tool," "Base," and "E85" packs.

It's important to follow the installation instructions at this step.

Next, you'll need a way for the laptop to communicate with your car, which will require an OBDII to USB cable. I bought this one:

https://www.ecstuning.com/b-ecs-parts/obdii-usb-diagnostic-cable/vt1a0003/

Once I downloaded and installed the software, I opened NCSDummy to feel out the waters, and here is where I am running into my next problem: I can't find the heated seat module.

There are many online, throughout the forums, listed: CAS, IKHA, etc., of which I have none. BUT,

I think this may be due to a few factors:
For starters, my laptop is not connected to my car. I've only ordered the cable today, and it will take a week or so to arrive. Secondly, the module that I placed into my car added heated-seat controls. So, I am hoping that once I hook my computer up to my car, a module will appear in NCS that allows me to activate the heated seat functions.

This is turning into a much larger project than I thought. Plug and play was the expectation, and now I am planning on coding my car.

Continuing my research, I came upon this article, which makes me think modding the module may be simpler than I thought:

https://www.ljcaesar.com/2014/01/changing-bmw-vehicle-order-using-ncs-expert/

If it is that easy, as typing in $494, and having the software handle the rest, my mea culpa may be on the horizon. I feel like this won't be the case, however.

For those stumbling upon this thread, I will update it once the cable arrives and I am able to begin using NCS with my laptop attached to my car. If anyone with greater knowledge than I sees this, please share your knowledge.

Sleepy


saving my research:

Heated power seat not working when swapped.

Heated power seat not working when swapped.

www.e90post.com

Heated seat not working - Z4-forum.com

Heated seat retrofit coding

Hoping to pick up a set of electric heated seats for my LE in the new year (rare as rocking horse ****!). As far as I know, with electric seats as standard it's just a case of swapping the seats out with the modules, adding the switches in the dash (already got), putting fuses in the fuseboard...

www.babybmw.net

USING NCS TO CHANGE VO.pdf (polish, just keep clicking download; it's another NCS guide)
NCS Dummy - Taking the expert out of NCS Expert (NCS dummy guide)

BMW Coding Forum

An active discussion forum providing information and resources for BMW Coding and diagnosis.

www.bmwcoding.com

BMW 645ci heated seat retrofit

Hi. Im Martin. I am about to fit oem seat heating into my 2004 645ci. Got the switch consol fitted, got the seat heater elements fitted and now struggling with the wiring. I've done days of research on the net but i cant find a solution for my case. As i seen everybody runs wires from under the...

www.bimmerforums.co.uk

 

[BimmurBrothor]

Well nice post...
Misery does love company.
I too am in the same boat as you.

But I am working on the e83.

I think I started back in September.
Researched , no simply compared the dash control panels and figured it's too much of a headache.
Later after reading more threads and finding several e83s at the boneyards and then I found a pair of dusty e83 seats but in the best condition for the age....the project is on again fiercely.
I've got to get ready for work...but I've found several post that are very encouraging. There's so much more to say on the subject...but it's doable and i think it's easier then we know.
Yours buttons blink!
Iam starting new
Finally, I'm at the point of simply going to the boneyard and removing the wires and transplanting them into my car.
Later here I'll post some of the posts that reignited my efforts.
Here's a main one, enjoy...

Pre-LCI Heated Seat Retrofit Questions

Hey folks, I have a set of heated, E63 M6 seats ready to install in my '99 328i. I've spent hours reading up on the topic and I've determined that that this retrofit is entirely possible with the right parts and coding to disable the passenger occupancy sensor. Seats fit great, trouble is, my...

www.e46fanatics.com

can heated seats be added to '07 X3

Just curious on this. What does it take to add "factory" heated seats? If I can buy a front seat with this option on it, what is needed to get this function? Are the required connectors in the existing wiring harness under the seat & in the dash panel? I assume there's a controller that would be...

www.bimmerfest.com

Heated seats retrofit.

Bimmerforums is the preferred online BMW Forum and community for BMW owners. At Bimmerforums, you will find technical how-to information maintenance specifics audio advice wheel and tire combinations and model specific details not found anywhere else. Our professionals are here to help make...

www.bimmerforums.com

DIY: Non-Heated to Heated Seat Retrofit!! Lots of Pics!!!

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...

www.e46fanatics.com

Start at 20:50 and enjoy more insight on retro fitting seats power...

Sent from my REVVL V+ 5G using Tapatalk

 

[sleepyonthehighway]

Here's a complete document list on how to retrofit the heated seats. Problem is, my car was not pre-wired for the heated seats. Here's a complete update:

After everything above, I had the car programmed by a wonderful dude out of Boston, and still the seats didn't work. That's when we realized the car did not have the wiring installed. The wiring harness doesn't have a part number, which will make this search extremely difficult. But that's all I have now after months of research.

 

[M_Bimmer]

....So, unlike many other retrofit guides, I shouldn't have to add any lines to the JBE or VO or whatever......

Sorry to disappoint, and as you have almost certainly found out, you need to install all wires and ECU that support the whole heated seat ciruit, which includes replacing the JBE.

BMW DOES custom make wiring harnesses and ECU's specific to the features purchased from the factory. They do not sell all variations of parts over-the-counter, but only choose the least number of part numbers that can support all vehicle order types to minimize their supply chain burden, but ECU's such as the factory installed JBE's have "do-not-populate" sections on their PCB's, so just installing wiring will not equate to success.

In the case of the Z4, if you look up JBE on RealOEM, you'll need the JBE part number that states "heated-seat = YES", which can be sourced "new" from BMW, or "used" from eBay.

Then ensure you've installed all the wires from the factory stated fuse(s) to the seat - ALL wires per TIS. You will not be able to buy a "retrofit" harness from BMW, unless you buy the whole cabin harness (impratical), so you can opt to run your own wires, or get a used harness of eBay.

Good Luck.

 

[sleepyonthehighway]

Sorry to disappoint, and as you have almost certainly found out, you need to install all wires and ECU that support the whole heated seat ciruit, which includes replacing the JBE.

BMW DOES custom make wiring harnesses and ECU's specific to the features purchased from the factory. They do not sell all variations of parts over-the-counter, but only choose the least number of part numbers that can support all vehicle order types to minimize their supply chain burden, but ECU's such as the factory installed JBE's have "do-not-populate" sections on their PCB's, so just installing wiring will not equate to success.

In the case of the Z4, if you look up JBE on RealOEM, you'll need the JBE part number that states "heated-seat = YES", which can be sourced "new" from BMW, or "used" from eBay.

Then ensure you've installed all the wires from the factory stated fuse(s) to the seat - ALL wires per TIS. You will not be able to buy a "retrofit" harness from BMW, unless you buy the whole cabin harness (impratical), so you can opt to run your own wires, or get a used harness of eBay.

Good Luck.

Replacing the JBE is a must even though I’ve programmed the computer to allow for heated seat functions, or am I misunderstanding a step here?

 

[M_Bimmer]

What's the part number on your JBE? I'll look it up...if it supports heated seats from the factory, then no replacement is required....but if it does not support heated seats from the factory, you'll need to get a JBE that supports heated seats....

But's let's check the P/N first.

 

[sleepyonthehighway]

Tried to get at it today, but couldnt figure out how to get the trim off on the inside of the glovebox. it was raining too, so i didn’t give it my all. will try tomorrow.