Speedo not working

Hi all,
Speedo has been working fine up until yesterday.

Yesterday I topped up all the oils, including the transfer box and gear box, and changed all the filters.

Last night I went for a short drive and the speedo wasn't working. I went back underneath and checked and cleaned the connection at the transfer box housing, and also the one slightly higher up on top of the transfer box. Both okay, but still no speedo.

The fuses are all okay so I'm stumped. The only things I can think of these:

-I removed the EGR yesterday and simply taped up the wiring which plugged into it. (black and red, pink, and blue and red wires IIRC).

-There is a spade connector just dangling in the engine bay, next to the connector which goes to the oil filter. It occured to me that I may have dislodged this when I changed the fuel filter but there's no obvious place for it to connect to.

I will be very thankful for any help as I'm supposed to be going 70 miles to collect some wheels today, and currently stuck with no speedo lol!

Quick update for anybody who encounters this problem in future:

I was getting 12 volts at the connector into the transducer, so ruled out the wiring, and the mysterious loose connector in the engine bay. I sprayed the connections with wd40, and gave them a good rub together, and took the car for a short run. Within about 50 metres the speedo came back to life, and although the speedo seemed slower and less responsive than normal (probably my imagination tbh), it is working. I think a new transducer might be on the cards before too long, but now to go get my wheels.

i have speedo issues on and off, all i have to do is remove transducer clean up and refit and all is fine again.