Can anyone tell me what temp the gearbox warning lamp should come on at on a TD5? And roughly the normal temp of the transmission oil? Just found my temp sensor was unplugged!

I believe this would cause a warning light if unplugged?

I dont know the exact closing point of the temp switch but according to Ashcroft the temps for the autobox are as follows :
Absolute maximum temperature (can result in damage) - 149*C (300*F).
Maximum allowable temperature for short durations such as a hill climb - 135*C (275*F).
Normal operating temperature range - 80*C (175*F) - 94*C (200*F).
Minimum operating temperature - 66*C (once the vehicle has warmed up from a cold start).