Skoda Yeti: Install Heated Windshield (Aftermarket)

Hello everyone,

After a few years of not using VCDS, I want to become active again. The reason is that I actually wanted my Yeti to have a heated seat and a windshield heater, but Skoda didn't offer that combination. I often find myself in the north during the winter, which is why I decided to get the heated seat. My plan was to have the windshield heater retrofitted after the first stone chip.

Last week, the inevitable happened: my windshield cracked. I immediately contacted several workshops, but my request was categorically rejected with the explanation that they only install the same type of windshield that is already installed.

Perhaps one of you has experience with this and can point me in the right direction. I've started doing some research, and currently, my understanding is based on the following information I've gathered from the internet:

There are original options for windshield heating or a parking heater, but not both together.

Most people who retrofit a parking heater choose a Webasto kit. However, I have also occasionally found original retrofitting options offered by Skoda workshops. The control can be either by replacing the Climatronic control panel with a corresponding button or via a remote control. I can't say for sure whether that was just talk.

When retrofitting the windshield (without a heated seat), the process is similar. You can either build your own solution, use an additional fuse and relay connected to the mirror or rear window heater, or use the original method by replacing the Climatronic control unit. The original fuse is number 28 in the engine compartment.

Kufatec offers a wiring harness (part number 47633), but there are no instructions included. I previously inquired about this.

In the Yeti, there is no Climatronic control panel that has both buttons. Either 3T0 907 044 CH for the defroster or AE for the auxiliary heater. However, in the Passat, there is. 5K0 907 044 BH has both buttons.

Sure, I'd be happy to help you with that. Please provide the text you would like me to translate from German to English. I will do my best to provide an accurate and natural-sounding translation.

My ideal solution would be to retrofit the windshield heating system as close to the original design as possible. This raises the following initial questions:

How is the original windshield heating system actually wired? Is there a separate control unit, or is it connected somewhere else?

What kind of cables do I need? Does the entire wiring harness need to be replaced, or is it enough to just tighten a few cables? When I look at the product from Kufatec, it doesn't seem too daunting.

How about the controls? The control panel with both buttons from the Passat doesn't fit into the Yeti, but the arrangement of the buttons and the connectors on the back are the same. Is it possible to somehow "retrofit" the button? Can the circuit board from the Passat version be installed into the housing of the Yeti version?

Vielleicht fällt euch dazu was ein. Best regards,
Christian.

Hi.

I can't understand why workshops are unwilling to fulfill a customer's request, especially when the customer is willing to pay for it. Who ultimately decides what gets installed, besides in cases where it's illegal within a certain framework?

Regarding the controls, I would implement it as it was originally done in our 99 Galaxy TDI. It would be a completely self-contained system, activated by a button. It would need to be re-enabled every time the engine starts, and it would also automatically shut off after a certain period to protect the vehicle's electrical system.

...I'm (unfortunately) no longer surprised by things like that. There are hardly any people left who really know what they're doing. If there's no error code with instructions on how to fix it, they're already stumped. Most workshops are only focused on making the most money with the least amount of effort.

Therefore, I hope you can help me.

I'm going to put the "DIY" option on hold for now. However, if there's no way to get it to look somewhat original, I would consider doing it myself. I suspect that the wiring harness from Kufatec might be suitable for the job.

Best regards,
Christian.

PS: The last glimmer of hope I had for the repair shop vanished when I visited our car club, the ÖAMTC, because my all-wheel drive system had stopped working. The mechanic told me it was fine and explained that the all-wheel drive only works if I turn off the ESC. After a lengthy discussion, I found myself surrounded by four mechanics who then explained to me that my all-wheel drive was working and that I couldn't even verify the function myself because if one wheel spins, all the other wheels are "deactivated." I was speechless and immediately canceled my membership. After repairing the Haldex pump and spending 500 euros, the all-wheel drive started working again.

Hello Christian,

The windshield heating is controlled via the button on the climate control panel, using the CAN bus system and the Body Control System (BNS).


This means you need to connect the Kufatec wiring harness to the BNS (body control module) and properly code the BNS and the climate control unit.

You've installed a Highline BNS here, so you don't need to change anything.

Compare the wiring diagrams of the two control units and, if necessary, rewire them.


You need the part from Kufatec with the part number 7L3.


Does that help you for now?


Best regards,

Michael.

Thank you, Michael, that actually helps me quite a bit.

Now I know that the wiring harness is not for a DIY solution, but for an original retrofit. I also received a message from Kufatec stating that there is currently no instruction manual available, but they will create one that can be downloaded directly from the product page.

The issue with the button isn't quite so simple. I have the original auxiliary heater installed, so the button is already assigned to another function.

The second button, located on the left side, is not available on the Yeti. That's why I asked above if it's possible to add it. Or, could a control panel from a Passat, which has both buttons, be installed instead?

What would probably work is to replace or reprogram the control panel so that it activates the windshield heating. Then I would have to use the remote control to turn on the auxiliary heater.

Where can I get the wiring diagrams? The last time I worked on the car (in 2017), you could rent access to the service manual from Skoda directly for a small fee. Is that still available, or are the diagrams now publicly accessible somewhere?

Thank you very much and best regards,
Christian.

Pumuckl wrote:

The second button, on the left side, does not exist on the Yeti. That's why the question above is whether it can be retrofitted? Or can a control panel from a Passat, which has both buttons, be installed?

I suspect the problem lies with the software for your control panel. The Yeti Climatronic software seems to expect either the FSH or the STH function to be assigned to the left button. That means, even if you add a second button, the software will likely not be able to interpret it correctly.

Pumuckl wrote:

What would probably work is to replace or reprogram the control panel so that it activates the windshield heating. I would then have to turn on the auxiliary heater using the remote control...

I wouldn't even be sure about that. If the control panel doesn't support STH (presumably a specific feature or technology), it might also not activate the fans and dampers when STH is enabled (e.g., via remote control).

Pumuckl wrote:

Where can I get the wiring diagrams? The last time I was working on the car (in 2017), you could rent access to the service manual from Skoda directly for a small fee. Is that still available, or are the diagrams now publicly accessible somewhere?

Can you still purchase a short-term access to VW vehicles at a low price?


The Passat control unit supports both buttons, at least in terms of hardware and software. Therefore, I think this gives you the best starting point. However, it will be interesting to see whether this control unit can be properly coded for the Yeti. I suspect there will be some incompatibility here, and no one can predict which Passat control unit has the best chance of being compatible with the Yeti.

In short: I believe it's possible that there might not be any software that supports both buttons and all Yeti control units/Yeti CAN messages. However, I am absolutely not an expert on the extent to which Passat and Yeti CAN messages differ.

Hello Christian,

Don't stress yourself out about it. You've taken on a great project. You can modify it. You need to compare the wiring diagrams and PR codes of each control panel beforehand.

If you find it easy to compare wiring diagrams and have some understanding of the CAN bus, it's not that complicated.

I installed the climate control unit from a Golf 6 into a Touran 1T1. When controlling the recirculation flap, I had to install a potentiometer because the control signal wasn't compatible. The Touran originally had a simple air conditioning system and was supposed to get an automatic climate control system. Also, the Touran didn't have an air quality sensor. I had to replace the BNS (Body Control Module) and the Gateway. Even with the Touran, simple coding was enough to make everything work.

You already have a Highline vehicle, which means the BNS and Gateway are Highline versions. You have an air quality sensor installed in the vehicle. The costs remain manageable.

You need the Kufatec wiring harness for a vehicle WITHOUT a start/stop system. The Kufatec wiring harness essentially only has three wires: a wire to the fuse, a ground wire, and a control wire from the BNS (Body Control Module).

You need to make sure that the climate control unit supports all the functions. The PR codes must be correct.


If you experience any problems with the auxiliary heater, you can use a (GSM) remote control.

You can also read the CAN command for the auxiliary heater from the old climate control unit and use a CAN-compatible relay to implement it.

This means the relay reacts to the CAN command from the Passat (which may not be compatible) and sends the correct command from the Yeti onto the bus.

However, the differences within the platform are likely not to be that significant.

You can test this very well using Rainer's CAN tool.



Best regards,

Michael.

Hello Michael,

I ordered the cable before. If I have time this weekend, I'll take apart the control panel and see if it's possible to replace the Braille button.

It would be interesting to see if anyone has photos of the circuit board from the Passat part with both buttons. I've searched on the usual online marketplaces, but there's nothing for sale at the moment.

If I can't manage to get everything working, I could recode the control panel to work with the windshield heating system and operate the auxiliary heater with the original remote control. I already have that remote, and it should work independently.

Or I could intercept the signal from the rear window heater and send it to the windshield... I already did something similar in 2015 for an Android navigation system to turn on and adjust the volume of the original sound system. Back then, I even built the hardware myself and hid it behind the glove compartment. Is there anything ready-made available now that can perform such tasks?

Best regards,
Christian.

Hello everyone,

"I finally found some time today and wanted to install the wiring harness. After removing the battery and the electrical box, I wasn't sure where to mount the included relay holder... As far as I can tell, the original relay should be located next to the glow plug relay."

I contacted Kufatec and I'm curious to see what their response will be. I've attached a few photos below, maybe someone has an idea...

Best regards,
Christian.

Hello Christian,


It's just as you suspected.

The relay for the windshield (J47) is mounted next to the glow plug control unit (J179) in the free space within the electrical box.

Best regards,

Michael.

Hello Michael,

Yesterday, I was still looking through the parts lists, and it looks like I need relay 3B0 951 253, socket 3C0 973 721, contact terminals, and screw N 907 676 02.

The Kufatec wiring harness looks completely different; it has a relay bracket for 3 relays, and it can only be mounted somewhere that is dry and dust-proof. However, the wiring harness looks like someone put some thought into assembling it, so I suspect that it's either for a different car or it will be installed somewhere else. I'll keep you updated.

Best regards,
Christian.

Good morning, Christian,

Did you receive a wiring diagram from Kufatec?

According to the manufacturer's specifications, the relay should be located in the electrical box.

When you install it inside a BNS unit, the cable runs are shorter.

The terminals should be connected as follows:

85 - to BNS T52b/23 rt/sw 0.5

86 - to the voltage stabilizer (J532) located under the seat at T12o/7.
DC 2.5 rt/bl

87 - goes to the windshield.

30 - connects to the fuse holder SB28 (50A fuse) T40a/4 rt/gr 6.0.


What did you get? Is there an instruction manual for it on the Kufatec website? Maybe you could take a picture of the installation kit.

Best regards,

Michael.

Hello Michael,

I purchased the wiring harness 47633 7L3. There is also a variant 7L6 available. There is no wiring diagram for either, but there is an instruction manual.

"There, it says I should attach the relay holder in the electrical box in the engine compartment. The electrical box contains all the fuses, and I haven't found a place where I can clip the relay holder in. I can't imagine that it means I should just put it inside the electrical box and secure it with cable ties or something similar. Especially because there's an original relay holder with space for a relay underneath the electrical box..."

Furthermore, the cables for SB28, SB8, and T52B are approximately 1.5 meters long and are bundled together.

Looking at the wiring harness as it is, it seems the idea was to mount the relay somewhere in the engine compartment on the driver's side. From there, two wires would run to the window, and the three bundled wires would be routed into the driver's footwell and connected to the control unit and fuse box. However, that would be completely different from the original setup.

Underneath my driver's seat, there's the amplifier for the original sound system. I don't have the automatic start-stop function.

I'm curious to see what response I'll get from Kufatec.

Best regards,
Christian.

While looking up the original part numbers, I also noticed the following: In the original wiring diagram, the main cable is shown as 6mm², which then reduces to 2.5mm² for the connections to the lights. In my wiring harness, all the cables are the same thickness, and they are likely 2.5mm² in cross-section.

Okay, I'm starting a list of the original parts here. I think I'll need the following, but I'm not sure about the plugs and connectors:

3B0 951 253 - Relay
3C0 973 721 - Relay module.
357 972 742 - Inserts for 0.5mm² cables.
257 972 742 B - End sleeves for 2.5mm² cables.
257 972 742 C - End sleeves for 6mm² cables.
071 973 851 - Steckergehäuse f. Disc.

4.8mm Flachstecker Crimp-Kontakt f. Disc.
4.8mm crimp contacts for 0.5mm² wire.
T52B/23 crimp contact for 0.5mm² wire.
9.5mm crimp contacts for 6mm² cables.

Cable 6mm².
Cable 2.5mm²
Cable 0.5mm²

I got the part numbers from the internet. Is there any trick in Erwin (siehe Fehlerdatenbank) to easily access the spare part numbers? If so, I'll take another hour to find them.

Best regards,
Christian.

Hello everyone,

I've made significant progress with my windshield heating system.

As I mentioned before, the wiring harness from Kufatec was nothing. They "examined" the issue for 5 weeks and then informed me that they were revising the wiring harness. So, with a bit of luck, future customers will receive a suitable set.

In the meantime, I managed to source the necessary parts myself and installed everything. I left the two cables to the windshield long so that the guys can cut them to the correct length and crimp the connectors when they replace the windshield.

On Thursday, the window was finally installed. Today, I programmed the window into the vehicle's control unit and installed a control panel with a button for the window heater. So far, everything is working well, and the window is heating up.

However, I still have a few questions.

The device draws approximately 50A, and it's also protected by a 50A fuse. Consequently, the fuse gets quite hot. Does anyone have any experience with this? Are there perhaps special maxi fuses with lower voltage drop? Otherwise, I might consider switching to a 60A fuse.

"I no longer have the dedicated button for the auxiliary heater. However, I can turn it on using the remote control. But the climate control unit doesn't seem to recognize it, and it doesn't activate the fans. Is there a way to make it work? I briefly checked the coding assistant, but didn't find anything obvious. As soon as I have time, I'll clear all the error codes and post a current scan of the car's systems. Right now, the climate control unit still shows error codes from the previous car..."

Best regards,
Christian.

Address 08: Climate Control/Heater (J255)
Label file: | DRV\5K0-907-044.clb
Part number SW: 3T0 907 044 CJ, Hardware: 3T0 907 044 CJ.
Component: Climatronic
Part number: H19 0709
Revision: 00001009
Encoding: 0010000003
Operating number: WSC 33361 790 00999
ASAM Dataset: EV_Climatronic A01010
ROD: EV_ClimaAutoBasis_SK35.rod
VCID: 7CF05B27F78A426F90-8028

Attached is the scan of the new control panel.