Whats this warning light..?

I have just replaced the clutch and gearbox in my 1980s 200TDI 110 CSW and it appears I have a warning light I didn't know existed. It's not in the handbook and I can't find it online...

It is RED, that's the first thing. It consists of a gear wheel with a drop of oil in the middle (like a tear drop) both of which overlay a vertical thermometer.

To me it seems to suggest the gearbox oil temp is high...but I don't recall there being a sender for this parameter, so...

Thanks

David

Gear box temp but UK models were not fitted with the sender,you may have trapped a wire some where.

^^^ wot he said

Thank you!!