About 6 months ago, I installed an OE used but in mint condition central lock system in my 240. Everything was ok until recently. I use the driver side door central lock system to open the rest of the doors, there is quite a delay before the rest of the doors open. Sometimes about 3-5 seconds delay before the these doors open, sometimes it takes over a minute.

What seems to be the problem? My friends jokingly say my 240 is possessed.