Facelift A3 2.0 tfsi quattro retrofit S3 rear diff with quattro mode select option

Alexey

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Hi guys. I need your help.
I'm trying to find any information about the possibility of coding an option "quattro mode" in Drive Select.
I realized that this option at least needs a sport differential from s3.
That is, I have to replace my differential FM0 to FN0 but I do not know in which control units it will be necessary to code this option.
I did not find anything like this by searching in Google, have any ideas?
 
You need the dealership to actually load the software into the car to make the Audi drive select to work. I had Quattro but to get ads, you have to retrofit the software too.

I would think it would also require a bunch more sensors too as the car needs to know when the front is skipping to turn on the haldex.

Big job overall.

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You need the dealership to actually load the software into the car to make the Audi drive select to work. I had Quattro but to get ads, you have to retrofit the software too.

I would think it would also require a bunch more sensors too as the car needs to know when the front is skipping to turn on the haldex.

Big job overall.

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I already have an option Audi drive Select, i need just add more options in this function. I also already have quattro from factory. The only task is to change the type of rear differential (FM0 to FN0). I doubt that I will need additional sensors, since the difference is only in the software part, I have no opportunity to switch haldex maps, but guys with S3 FL can do this (also on RS3).
 
I don't understand, you want to change the haldex? There is no difference really as it's all software which can't be updated realistically.

Would be best to get a haldex controller for your current.

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I don't understand, you want to change the haldex? There is no difference really as it's all software which can't be updated realistically.

Would be best to get a haldex controller for your current.

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I'm afraid that there are some differences in the housing of the rear differentials, so a simple replacement of the controller will not work, I found a whole differential for little money.
 
I'm afraid that there are some differences in the housing of the rear differentials, so a simple replacement of the controller will not work, I found a whole differential for little money.
They are both the same. Is your current one bad? Had you checked the pump? There is a screen that gets clogged.

I'm not fully understanding what you are trying to gain to answer your question correctly.

I was taking about aftermarket handed controllers similar to this one. https://www.shopdap.com/haldex-controller-mk7-mqb-gen5.html

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They are both the same. Is your current one bad? Had you checked the pump? There is a screen that gets clogged.

I'm not fully understanding what you are trying to gain to answer your question correctly.

I was taking about aftermarket handed controllers similar to this one. https://www.shopdap.com/haldex-controller-mk7-mqb-gen5.html

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I mean differences in factory controllers and differentials, I know there are aftermarket solutions. But I want exactly the factory version from s3.
My differential is fine, no malfunction.
 
I mean differences in factory controllers and differentials, I know there are aftermarket solutions. But I want exactly the factory version from s3.
My differential is fine, no malfunction.
Again, there is no advantage as they are the same generation of haldex and can only supply so much distribution. You will have to do swop changes which you still won't get much advantage out of.

The new a3s 2021+ will have more aggressive haldex couplers that will allow better "drifting" attributes.

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Again, there is no advantage as they are the same generation of haldex and can only supply so much distribution. You will have to do swop changes which you still won't get much advantage out of.

The new a3s 2021+ will have more aggressive haldex couplers that will allow better "drifting" attributes.

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There are more differences than you might think. Different strategy in the same 5 Haldex generation. That is, despite the fact that there are many VAG models on the 5th generation, this does not mean that haldex strategy map the same everywhere. In order to understand it is enough to watch a video of the behavior of different models with haldex5 in the snow. You can also understand that the part numbers of the controllers and the differentials are different in ETKA.
 
Why u just don't get an S3? Saves you messing around..
Sell current get real deal....
 
Why u just don't get an S3? Saves you messing around..
Sell current get real deal....

Because I live in Russia ... ((( We have huge problems with the choice of cars. After the 14th year, our audi model range has been greatly reduced.
We don't have s3 FL, rs3 FL. And many others interesting cars. Everything is so bad that there are probably only 2-3 Audi A3 FL 2.0 tfsi quattro sportback for the whole of Russia.
 
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Because I live in Russia ... ((( We have huge problems with the choice of cars. After the 14th year, our audi model range has been greatly reduced.
We don't have s3 FL, rs3 FL. And many others interesting cars. Everything is so bad that there are probably only 2-3 Audi A3 FL 2.0 tfsi quattro sportback for the whole of Russia.
Unfortunately these cars are computers on wheels and require so much coding that isn't readily available without expensive machines.

I wish we could just swap parts from other models and call it a day but doesn't work that way from all the component locking.

Sent from my Pixel 3 XL using Tapatalk
 
Unfortunately these cars are computers on wheels and require so much coding that isn't readily available without expensive machines.

I wish we could just swap parts from other models and call it a day but doesn't work that way from all the component locking.

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I do not know how you imagine the swap process. But we have alot of swap projets in Russia on MQB platform )
Retrofitting a front-wheel drive vehicle with all-wheel drive does not seem to be a problem on MQB. It's not even interesting to talk about various wild options for swap engines and transmissions on the PQ35 platform. Therefore, I think that replacing the rear differential is not a problem, the problem is only in the coding, so far there have been no incidents.
 
I do not know how you imagine the swap process. But we have alot of swap projets in Russia on MQB platform )
Retrofitting a front-wheel drive vehicle with all-wheel drive does not seem to be a problem on MQB. It's not even interesting to talk about various wild options for swap engines and transmissions on the PQ35 platform. Therefore, I think that replacing the rear differential is not a problem, the problem is only in the coding, so far there have been no incidents.
The physicals of this are not going to be an issue, even the coding is going to be pretty simple. The issue is going to be everything related to software. I cannot assist, as per my email, unless you want to ship me the car.

Speak to these guys, they are local to you:

https://instagram.com/vagler_russia?igshid=1tjwc8b02s86u
 
Because I live in Russia ... ((( We have huge problems with the choice of cars. After the 14th year, our audi model range has been greatly reduced.
We don't have s3 FL, rs3 FL. And many others interesting cars. Everything is so bad that there are probably only 2-3 Audi A3 FL 2.0 tfsi quattro sportback for the whole of Russia.
You can go to europe pick an S3 and take it to russia :)
 
You can go to europe pick an S3 and take it to russia :)

Hahahaha )))) And now I will tell you a sad story about the cost of customs clearance for cars in the Russia.
For example if i want to buy used s3 for 25k euro i will need to pay 12k euro for customs tax...
 
The physicals of this are not going to be an issue, even the coding is going to be pretty simple. The issue is going to be everything related to software. I cannot assist, as per my email, unless you want to ship me the car.

Speak to these guys, they are local to you:

https://instagram.com/vagler_russia?igshid=1tjwc8b02s86u

I talked with these guys today, they said that they were not interested. There is a rather big problem in the fact that in our country everyone who is engaged in retrofitting is mainly engaged in "in-line retrofitting" (navigation, electric mirrors, parking assist, etc.), they do not tackle the complex or unusual.
 
I’m curious what is there to be gained from a rear diff from a s3? what’s the difference between the a3 and s3 diff?
Better handling/traction etc? Or just another menu on the MMI?
 
I’m curious what is there to be gained from a rear diff from a s3? what’s the difference between the a3 and s3 diff?
Better handling/traction etc? Or just another menu on the MMI?

Better haldex coopling strategy, more oversteer car behavior.
 
Hahahaha )))) And now I will tell you a sad story about the cost of customs clearance for cars in the Russia.
For example if i want to buy used s3 for 25k euro i will need to pay 12k euro for customs tax...
Ridiculous.. Tell putin ; This is MADNESS :D
Btw, used S3 do not cost so much 25k .. I believe you can get cheaper .. below 20k
 
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I’m curious what is there to be gained from a rear diff from a s3? what’s the difference between the a3 and s3 diff?
Better handling/traction etc? Or just another menu on the MMI?
Again, there is no physical difference in the actual haldex units. It's a just swop software enabling the amount of time the unit pumps turn on and engage the clutches from the drivetrain canbus signals.

These units also cannot provide over 50% of power to the rear as the car is front biased.

There is alot of info on this generation of haldex system.

For the OP, it's cheaper and easier to actually get the haldex controller as the oem software he is seeking is the headache.

Part numbers for 2015-2020 A3, S3:
Differential: 0CQ-525-010-S
Differential control module: 0CQ-907-554-J

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Hahahaha )))) And now I will tell you a sad story about the cost of customs clearance for cars in the Russia.
For example if i want to buy used s3 for 25k euro i will need to pay 12k euro for customs tax...

Import / reregistration taxes are huge.

I met someone who had his bike registered in Estonia and had to do a 1200 mile round trip once a year from Russia back to Estonia to keep it registered there.
 
Better haldex coopling strategy, more oversteer car behavior.

for the cost and effort involved is it worth it?
For everyday driving unless you track it will you notice the any real world difference ?
I drive my s3 pretty hard when opportunities arise and I can say most Quattro Audi’s are designed to go understeer first not oversteer. S3 is probably the worse for trying to get oversteer as the chassis is short/compact Compared to my old longwe a6 Quattro where it’s was much easier to swing the extra weight/length out.
 
Ridiculous.. Tell putin ; This is MADNESS :D
Btw, used S3 do not cost so much 25k .. I believe you can get cheaper .. below 20k

Putin did not care about the problems of slaves ))) So far, the most budgetary method to get s3 in Russia is to build your own s3 :rock:
 
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for the cost and effort involved is it worth it?
For everyday driving unless you track it will you notice the any real world difference ?
I drive my s3 pretty hard when opportunities arise and I can say most Quattro Audi’s are designed to go understeer first not oversteer. S3 is probably the worse for trying to get oversteer as the chassis is short/compact Compared to my old longwe a6 Quattro where it’s was much easier to swing the extra weight/length out.

So this is the interest, the cost of this tuning is relatively small.
I found a complete rear gearbox set for 600 euros.
I am not interested in how the car behaves in daily driving, I need to have fun on the snow in winter.