940 speedo suddenly working again after 7 years!

[Laney760]

I am having an intermittent starting problem in my 940 which I am just about to raise a thread about. My car was having difficulty starting after work today, cranking without firing, so I decided to put back my old fuel pump relay which was in the car still since fitting a new one last October. The old fuel pump relay made no difference to the starting difficulty and the car eventually fired up, eliminating the fuel pump relay from the starting causes.

Anyway, my speedo has not worked since 2012. I returned the car to the seller shortly after purchase and he repaired the speedo by working on the circuit board behind the dashboard. His repair lasted a short time before failing so I have always assumed that the board was the problem BUT after inadventently moving some wiring in the vicinity of the relay / fuse board behind the ashtray today my speedo suddenly came to life after seven years and worked ALL the way home!

Perhaps someone can enlighten me as to how my wiggling the wires around in the area of the fuse / relay board has bought my speedo back to life, what might be the cause of the original problem please?