Big problem s-tronic

[AngelA5]

Hi everyone, sorry for my english.
I bought a 2010 Audi A5 2.0 tfsi 155kw with an oil bath 7-speed S-tronic automatic transmission.
Very nice car but it has a problem that I didn't notice when I bought it and it's too late now.
In practice, when I stop at a traffic light the car remains in traction, in fact if I pass from D to N it gives a strong blow, in fact as soon as I release the brake it starts immediately while in reality it should go into traction an instant after releasing the brake.
This leads to overheating of the clutches.
Once the clutches are overheated at each stop it has a strong blow.
I have done several tests, the gearbox returns to perfect working order if it expends the passenger compartment air regardless of the use of the conditioned air.
Just simply set the choke to 1 and the gearbox goes crazy.
It looks like an electrical problem related to the cabin air.
I also changed the battery and alternator but no changes.
Any suggestions?

 

[NHN]

Irgendwelche Protokolle?

 

[AngelA5]

Irgendwelche Protokolle?

with the VCDS no errors

 

[AngelA5]

Irgendwelche Protokolle?

Sorry..
There is a 01206 error code in the air conditioning module electronics.

However:
The gearbox works perfectly if I press the OFF button in the selector for the air.
So absolutely everything turned off.
I'll give you an example.
As soon as I turn on the passenger compartment air, the gearbox will start to malfunction again.
If I am stationary, brake pedal pressed and D engaged, with the passenger compartment air off, everything works, if I turn on the passenger compartment air, the clutches begin to engage and the car enters traction.

 

[desertstorm]

Possibly a seized air con pump . The gearbox responds to the calculated torque value that is generated by the ECU . If the aircon pump is faulty and increases the engine load a lot when it is engaged, the engine has to produce a lot more torque to maintain the idle speed. The Gearbox would see this as the signal to pull away.
If you put your foot on the brake then it shouldn't engage the clutches to pull away.
Does the aircon actually work correctly and produce cold air? .

 

[AngelA5]

Possibly a seized air con pump . The gearbox responds to the calculated torque value that is generated by the ECU . If the aircon pump is faulty and increases the engine load a lot when it is engaged, the engine has to produce a lot more torque to maintain the idle speed. The Gearbox would see this as the signal to pull away.
If you put your foot on the brake then it shouldn't engage the clutches to pull away.
Does the aircon actually work correctly and produce cold air? .

The conditioned air works perfectly, the air is very cold.
The problem is when I turn on the air in the car, inside the cabin: hot, cold or the air conditioner
I'm thinking about the mechatronics and the two clutch solenoids.
But I did the automatic transmission wash 3 times.
Adaptations of clutches, pressures, etc.
Furthermore, the problem only occurs when I turn on the air in the passenger compartment

some time ago I had this code: P068A00
it happened when the battery left me on foot, replaced and coded but the problem does not change
I deleted this code, it never reappeared

 

[desertstorm]

I actually don't think your problem is in any way related to the gearbox . It all works fine when the heating isn't switched on. If you have VAGCOM you can look at measuring blocks. Have a look at the torque figures that are being seen by the dsg gearbox. The ECU outputs a torque value and makes corrections based on load . Be interesting to see what the figure does as you switch the aircon on and off.

 

[AngelA5]

The battery voltage changes from 14.3 to 13V when the air fan is turned on.
I'm afraid it's the bad battery.
Could be?