Hi, I'm a newbie here and need some help and advice.
I am working on a project which I have almost finished repairing. The car A8 3.3 tdi has a fault with the ECU (Output IC error) which means one of the engine ECUs is not giving a pulse to 2 injectors. So the car runs but is misfiring on 2 cylinders.

Bought a used ECU in order to replace it but need to retrieve the SKC from my old unit and the new unit in order to program it to my car (immobilizer).
Part number is 4D0 907 409C. I also have the instrument cluster and key with the replacement ECU if that helps but would rather keep the originals.

I purchased the Super K+Can tool to carry out Eprom read but have had no success.

Can anyone help please?

I initially replaced the injectors, moved them around believing it to be injector faults. There are 2 ECUs on this engine, one for each bank of 4. The other ECU also had a fault. I replaced it and the fault has since disappeared. Cylinders 7 and 8 get no pulse from the 2nd ECU which has the immobilizer. All wiring in order. There is a fault registered, 18012 Output driver IC error, which leads me to believe it has an internal fault. If it was a faulty injector or wiring I would get different error messages. Both ECU's have been exposed to rain because some idiot mechanic took the ECU compartment cover off and left the car outside for over a year.

Ok so nobody came back to me on this. Disappointing.
I'll share my knowledge. It's no mystery. The A8 3.3 TDI has the same immobiliser chip as any of the other Audis. So just de-solder your existing chip from your old unit unto the new one.
No need to buy complex cables and software programs.
Incidentally, some of the problems still remain after the ECU swap so I shall be checking my wiring next and then the injectors if the problem isn't solved.