A5 s line seats into a3 TDI

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
Anyone upgrade their seats to A5 seats? I just picked up a pair from a 2012 A5 s line. I'm going to tackle modding heated seats and power seat controls to the passenger side. Wiring seems pretty straight forward. Also picked up a few needed electrical plugs from eBay to make it as close to a factory job as possible. Ill try to put a few pictures up from the process.
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
A5 s line swap is almost complete. Airbags, passenger occupancy, seat belt switches, and all power movement functions including the rear forward and back switches are done and work on both passenger and driver. No codes. All I have left is installing the heated seat functions. I'm waiting on the correct electrical pins. Didn't have them in my scrounge. Seats fit great. HUGE upgrade over stock in fit, feel and functionality. Would love to write a guide in the future if I get time. Just for anyone else contemplating something similar, it is possible but it requires cannibalizing parts and modules over from the old seats. I also purchased a new climate module to upgrade the car to heated seats. You will obviously need to purchase the wiring diagrams from both the A3 and A5 as well.
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
Heated seats function is done. Works perfect. Had to run 3 wires per seat to the controller. Ordered the pins and plug pieces on eBay/alibaba. Lots cheaper than kufatec.
 

Nuje

Top Post Dawg
Joined
Feb 11, 2005
Location
Island near Vancouver
TDI
2002 Golf 6MT; 2015 Sportwagen 6MT; 2016 A3 e-tron 6DSG
Was the physical installation (i.e., seat rails and bolt locations) just a straight-across, no-fuss swap?
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
Was the physical installation (i.e., seat rails and bolt locations) just a straight-across, no-fuss swap?
Seat rails fit in once you remove an alignment pin on each seat. You are left with one alignment pin and 4 massive bolts on each seat, so I'm not concerned about security.
 
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SH41LZ

New member
Joined
Oct 30, 2024
Location
Harrow
TDI
Golf
Heated seats function is done. Works perfect. Had to run 3 wires per seat to the controller. Ordered the pins and plug pieces on eBay/alibaba. Lots cheaper than kufatec.
Did you manage to get it working with the OEM heating controls?

Cant seem to find a wiring diagram for the heated seats or airbags, I got the electric seat side of things working perfectly.
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
Yes. Everything works with the OEM A3 control panel. I took the a5 diagram and found all the needed wires and connected them up according to the A3 diagram. I had to take the plugs from my A3 seats and pin everything into them. I also stole the seat occupancy sensor and installed it into my a5 passenger seat so everything would work as if it was factory. All the wiring diagram are found on the Audi Erwin website.
 

SH41LZ

New member
Joined
Oct 30, 2024
Location
Harrow
TDI
Golf
Yes. Everything works with the OEM A3 control panel. I took the a5 diagram and found all the needed wires and connected them up according to the A3 diagram. I had to take the plugs from my A3 seats and pin everything into them. I also stole the seat occupancy sensor and installed it into my a5 passenger seat so everything would work as if it was factory. All the wiring diagram are found on the Audi Erwin website.
Did you have to use a relay to get the backrest heater working?, Seen a few guys on forums say they needed to do a relay mod to get the backrest to stay on for longer than 5 minutes, not sure exactly how they wired it in though.
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
Did you have to use a relay to get the backrest heater working?, Seen a few guys on forums say they needed to do a relay mod to get the backrest to stay on for longer than 5 minutes, not sure exactly how they wired it in though.
Didn't add a relay. Everything worked perfectly with the A3 climate module once the proper wires were connected. The only part of my seats that are not operational is the memory functions but that's because the A3 doesn't have the corresponding memory modules and switches.
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
Can you please write a detailed how to?
I'd love to have the time to but really don't.
The down and dirty:
Have both the new and donor car wiring diagrams off Erwin
Have either a set of donor plugs from stock seats or purchase some
Have donor occupancy sensor and module or purchase it
Have wire and pins on hand to add in heated seats function if your car doesn't have it from stock
Purchase a climate module with the heated seat function if you don't have it from stock
Cut off guide pin that doesn't fit into the floor on each seat
Install occupancy sensor into the new passenger seat
Remove old plugs off new seats and replace with new plugs for your car
Wire the plugs by comparing the two wiring diagrams. You will notice that both the A3 and the a5 seats have many of the same module/sensor labels in the drawings so it ends up being decently easy to do. Some of the wires are even the same color. I did a basic settings on the AC blend door when I was done because it's controlled by the new climate module and reset the airbag codes but that's about it for VCDS.
 
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relumalutan

Veteran Member
Joined
Dec 6, 2012
Location
Michigan
TDI
2011 Audi A3 TDI, 2006 VW Jetta (Sold)
No offense but that is a pretty wild ask of someone...
Makes me wonder what is the purpose of this forum then: for people to brag around about what they've accomplished with their car? Maybe I'm mistaken, but I thought the purpose of the forum is to help each other.

If you take your time to search my post history you will see that about 10 years ago I swapped GTI seats in my Mk5 and believe or not, I took my time to write a DYI for it.
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
It isn't a beginner friendly or quick mod. Also, depending on the exact vehicle and seats the wiring can vary quite a bit. If you've got the time and come across a nice set of seats for a good price I definitely recommend! Been over a year and I have thoroughly enjoyed having these in my A3. Love having the ability to fold the seats and slide them forward from the rear. I have two kids so it comes in handy.
 

Nuje

Top Post Dawg
Joined
Feb 11, 2005
Location
Island near Vancouver
TDI
2002 Golf 6MT; 2015 Sportwagen 6MT; 2016 A3 e-tron 6DSG
I'd love to have the time to but really don't.
The down and dirty:
Have both the new and donor car wiring diagrams off Erwin
Have either a set of donor plugs from stock seats or purchase some
Have donor occupancy sensor and module or purchase it
Have wire and pins on hand to add in heated seats function if your car doesn't have it from stock
Purchase a climate module with the heated seat function if you don't have it from stock
Cut off guide pin that doesn't fit into the floor on each seat
Install occupancy sensor into the new passenger seat
Remove old plugs off new seats and replace with new plugs for your car
Wire the plugs by comparing the two wiring diagrams. You will notice that both the A3 and the a5 seats have many of the same module/sensor labels in the drawings so it ends up being decently easy to do. Some of the wires are even the same color. I did a basic settings on the AC blend door when I was done because it's controlled by the new climate module and reset the airbag codes but that's about it for VCDS.
I feel like this is an excellent overview, and really - unless you're paying for their time, @McGuirk (or any "hey look at what I did") doesn't owe you anything. As stated above, it's not a beginner job, so if the basic steps outlined above are insufficient for you, doing this might be something to farm out.
Also, the potential audience for this is pretty small. If it something that might be doable by more members here, like TT seats into a mk4 Golf/Jetta :).....a person might feel like the investment of their time to do a DIY would be more warranted.
 

relumalutan

Veteran Member
Joined
Dec 6, 2012
Location
Michigan
TDI
2011 Audi A3 TDI, 2006 VW Jetta (Sold)
I feel like this is an excellent overview, and really - unless you're paying for their time, @McGuirk (or any "hey look at what I did") doesn't owe you anything. As stated above, it's not a beginner job, so if the basic steps outlined above are insufficient for you, doing this might be something to farm out.
Also, the potential audience for this is pretty small. If it something that might be doable by more members here, like TT seats into a mk4 Golf/Jetta :).....a person might feel like the investment of their time to do a DIY would be more warranted.
I was not aware that this is a debate forum, like Reddit for example. I asked the OP a simple question "Can you write a DYI?" Then suddenly people are starting to express opinions: "it's too much to ask OP to write a DYI", or "OP doesn't owe you anything". It's not other users' call whether OP should write a DYI or not, it's his call.

I don't feel like I was "entitled" to receive a DYI, that's why I kindly asked if a DYI can be written, which the OP also kindly provided at high level, enough for me to understand.

I am also aware that it's not a job for a beginner; if you read my post above, I mentioned that I already went to the same process with my 06 Jetta, where I swapped the seats from a GTI into, including connectors, passenger seat occupancy module and VCDS reset of the airbag errors.

With all due respect I feel like your reply is redundant and not necessary.
 
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Nuje

Top Post Dawg
Joined
Feb 11, 2005
Location
Island near Vancouver
TDI
2002 Golf 6MT; 2015 Sportwagen 6MT; 2016 A3 e-tron 6DSG
If all you'd done was ask "can you write a DYI?", that's a fair ask. I was going to ask the same thing.

Your passive aggressive
Makes me wonder what is the purpose of this forum then: for people to brag around about what they've accomplished with their car? Maybe I'm mistaken, but I thought the purpose of the forum is to help each other.
.... that's what made it sound like the OP "owed it" to the community here, and prompted my reply (which may have been unnecessary, but (to go full pedant), I don't see how it's redundant given that no one had made my points earlier in the thread. :D ).
 
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