Red oil light and message

[Mumzik]

After washing my engine I've got a red oil light and a message saying "STOP!Check oil level".
Oil level is fine. I think I've messed up with oil sensor.
Or may be something else?
How easy to replace that sensor? And where can iI find it under the hood?
Thanks.

 

[carfix]

i'm not sure about the 740, but on the 750 it's in the oil pan underneath..... try unplugging and cleaning the terminals... john

 

[jay76silver]

740 SAME LIKE 750