help oil sensor

[jonathan bees]

2002 passat tdi when you start the car the yellow oil light comes on and it says oil sensor workshop then after 5 seconds they go out till the car has been left for some time then started agan (checked and it is plugged in

[passing]

mine used to go off occcasionally about 50 - 300 yds after starting from cool or cold and could generally be cleared by ignition off and on again once to maybe 5 times. Though sometimes it would persist for no reason that I could find.
I was running it on 00w/40 at the time and since I went back to 5w/40 it has only happened once.