Ford Fiesta Dashboard Clock Cluster Error

Hello!
I have a 2007 FORD JC3 Fiesta Van 1.4 tdci MK5. Engine code: F6JB

My problem is that the clock often drops the hands, the LCD display disappears or "-" lines appear, or the immobilizer often flashes and the SRS light usually comes on.
It doesn't always do the same thing. The car doesn't even have to move, shake, run the engine or do anything, the clock just disappears and then the clock comes back.
I also resoldered the PCB-26-PIN connector, moved, pulled all the cables (at the clock unit and ECU, under the battery, in the glove compartment), checked all the fuses/relays, checked all the connectors (ECU, clock unit (26PIN)), but nothing solved the problem. I replaced it with an identical Ford clock unit, but it did the same thing, so it's probably not the clock.

Has anyone had a similar problem?
Does anyone know a wiring diagram for the 26-pin clock connector?
Or maybe an electrical diagram for the car that shows where the wires come from and what colors they are?

Thanks a lot for your help!