car turning over but wont start

hi everybody

im new to this site now so dont slaughter me ha

i bought a vw jetta mkIV a year ago. 1.9 tdi 100PD and today it decides not to start.
plugged it in to VAGCOM as there was a heater plug light flashing on the dash (also engine fault light) and i got.. 01314 - Engine Control Module.

when i looked into it further it says there was no speed sensor signal but i didnt think a speed sensor would stop a car from starting?

can anybody help

replaced speed sensor on top of the gearbox and still wont start anybody??

Not sure which engine you have in your PD over there, but if its similiar the the North American BEW PD than it sounds like you replace the speed sensor on the transmission instead of the engine. The engine has its own sensor. Its the "Crankshaft Speed Sensor or Engine Speed Sensor". Its located behind the oil filter housing, down toward the bottom of the block toward the rear bell housing. We had one fail on our BEW PD and it shut the engine down very frequently.