Question:
I tried today to make a keyless key on a Mercedes benz s350 2009 with xhorse vvdi mb and FBS3 key. but the keyless function does not work, error: The key is not recognized.
At the same time, only keyless does not work (The central lock is working by inserting the key into the ignition lock, the car starts, the doors close/open if you press the buttons). Keyless go did not!!!
Solution:
Change FBS3 key frequency does not work. It is not a problem of frequency.
Neither Xhorse nor CG keys will work for older non-BGA cars before 2009.
You need original for those.
The keyless function will not work if the original key has two batteries, you need to use the original factory key to prepare new key.
If original key has 2 batteries, you can't program keyless key to car. If 1 battery which is BGA key, you can program xhorse or cgdi keyless mb key.If you generate OEM key, not Xhorse key but had problem with OEM key keyless function, check following tips: