This is the simplest way to install the control unit for AC without requiring coding. Coding for this module is done with the diagnosis dedicated to this brand and is with an online account. Use CG Pro 9S12 to read eeprom 93C86. Because if by mistake the 93C86 memory is heated too much, it will lose the data.

Have a climate control unit from Audi A6. It’s C4 or 4f. It has water damage and comes to smoke.

Usually this can be programmed on the car, and it needs to connect and code online. But if there is a new one to change the original one, just swap the eeprom inside.

Remove all the screws, and remove the board, search the eeprom near to flash, and swap it with another new one, and install to the car.

The eeprom is 93C86.

It’s a safety job, no need to making coding or others. Use a bit of flux on the eeprom, and use a hot air gun and Tweezer to remove the original chip.

Put the chip into the EEPROM&V850 Adapter, plug the adapter to CG Pro 9s12 programmer, connect the power supply to CG Pro, and connect to PC.

Run CG Pro software, select Chip>> Storage Chip>> 8 PIN>> 93C86>> Read

Read the eeprom data and save it

Use the same procedure to unsolder the eeprom from the new climate control unit. Use a pen to remark the position, and solder the original eeprom on the new control unit. Restore it as before, and install it back to the car to test. It works fine!

Credit to@ YOYO Diagnostic!