BMW Multi Tool, Best Key Programmer For CAS3+ CAS4 All Key Lost

BMW Multi Tool Key Programmer, best device for BMW cars, such as CAS3+ CAS4, even all key lost, if you know more about key programming, it can help you more than key program.

Multi Tool for BMW OBD2 CAS1-3+ KEY PROGRAMMER V7.7 Support Encrypt CAS3 And CAS4

Let’s read his experience as follows:

Answer to the first paragraph’s question: Donno about AVDI, but its an easy job with BMW Multi Tool and i can confirm i have done many with Istap 45. Not by OBD all of it and not eeprom JOB, i use multi tool to downgrade the CAS on table by CAS plug and 12V, then i make key, downgrade process takes 30 min, making key takes 1 minutes the whole job is 31 min without opening the CAS.

I can do CAS4 all key lost as well with Multi tool, but u need the help of a DME, 10000% Success, job done on table, ADD key by OBD. I m using Dialprog, done 1 all key lost and 3 add key , not a lot of testing but so far so good.

Questions and answers:

To help more people know more details, I list some frequently-asked questions and followed by my real operation procedure/experiences.


Does the BMW Multi Tool make a save/backup of the CAS data before downgrading? I’m just wondering what happens if something goes wrong within that 30 min downgrade process?

Answer: Multi tool gives u note message before downgrading to use a programmer and save data (i always skip that message cz in case anything goes wrong i can reflash the cas) i can’t say how many BMW i’ve downgraded and NONE at all had a single problem, 100% safe. I never cared if the flashing process on the Multi Tool works or no or if it kills the cas since i have a backup the BMW Explorer. but i always choose the Multi Tool since its faster in downgrading cas.

BTW, I have BMW Explorer full kit cost about 10K. in 1 word. THE BEST for bmw

PS: u dont need manual. its very easy to use , even a kid can use it.

Question: so we downgrade using Mult-Tool – any extra cables/connectors required ?

Answer: no special cables needed except the CAS PLUG and 12v

Question: Do you do key programming by CAS plug or do you put it back in the car first?

Answer: u can do it by CAS plug, but i always plug it in car and and add it by OBD.

Question: Once you downgrade the cas to make the key is there anyway to then upgrade it back to version 45? I’m just thinking if you leave the car downgraded and it gets stolen a few weeks later you’ll have some explaining to do.

Answer: No you can’t unless they go back to dealer. Of course no downgrade is 100% safe. Obviously doing on table better tho. Haven’t we got a list of flashes on avdi which we can use to ensure safe(r). Here when a car is all key lost the customers doesn’t care if u make them only.  transponder, they just want their car running.