Nissan Largo Friends

From what I have read in the past it sounds like the temp sensor in the gearbox but just a stab in the dark??

i seen a thing on japsite for that by placing a resistoer inline to fool it ?

Problem with resistor is it changes gear when cold as it would when hot which could create more problems if it was the temp sensor it is located under the sump on the solonoid block not hard if you are brave! I heard of someone paying £700 to have it done! Daylight robbery if you ask me for a sensor that costs less than £30