It's my pleasure to join here. According to my S40 MK1 as bought last year. I could not use for central lock, thus had a second hand keyless entry box from ebay, so it works the central lock. However, the original remote can not use. (..did try to fix the broken keyless entry box on the pcb, and the keyfob was able to use just a second. Perhaps, the pcb connect is out of control)

Any methods, to DIY to tune the original keyfob to new keyless entry box?

Many thanks in advance.

Nop

 

Yes - you simply need the packaging the remote came in when it was new. (the plastic bag) On the bag is a code that is used to program the car to accept the signal from the "new" remote. That process is done with a VIDA subscription (and a DICE unit)