BMW CAS3+ to CAS3 Downgrade AKL Programming by CGDI BMW

Here share the guide on how to use CGDI BMW Prog to do all keys lost programming for BMW CAS3+ to CAS3 without downgrade risk.


Tips and guides to program keys:

Step 1: Read DME ISN

Step 2: Read CAS3+ Key Info

Step 3: Program key

Step 4: Test


Step 1: Read DME ISN

Plug the cable (DIY by professional technician) into the engine computer

Then Connect CGDI Prog BMW via OBD

Adjust the voltage to about 13V or 14V

Then pass on the power supply

cgdi-prog-bmw-msv80-do-all-keys-lost-1 cgdi-prog-bmw-msv80-do-all-keys-lost-2


Open the CGDI BMW software

Access to BMW ISN

If you know the ECU type, you can select the corresponding option.

Otherwise, you can click on Read DME ISN directly.

Capture the screenshot and save



Step 2: Read CAS3+ Key Info

Put the cable and engine computer aside

Plug another cable (DIY by professional technician) into the CAS ECU

Then Connect CGDI Prog BMW via OBD

Adjust the voltage to about 13V or 14V

Pass on the power supply


Select CAS1-3+ Key Match> Read Key Info

Pay attention to the prompt:

The current CAS version needs to be demoted by programming, whether it needs to be demoted or not, and programming CAS. Please confirm that the car has enough power, and it is forbidden to disconnect the device during programming.

Then click YES”


Wait 10 minutes…

Prompt “Please remove the key from the ignition switch” and click OK

Read key info success

Select the second mode to get ISN code

Enter the ISN code saved in the screenshot correctly

Then click Next”



Step 3: Program key

Put the blank key into the CGDI BMW Programmer coil


Return to desktop and click OK”

Check the prompt warning massage:

Whether the key currently programmed is a smart key?

Note: If is a smart key, the key will be locked!


Wait to program the key process completing

Program key success


Select CAS3 Key Match> Check Key State

Show key is locked


Step 4: Test

Now start to test


Test successfully

Author: admin