I totally agree with you that there are a lot of test to be maid before the engine is even started. All of those test will be in my plan be for a computer is bought!!! The warning light that is on the tach is above what looks like a old oil can. The manual says that it means there is a clogged oil filter. The oil filter is new the tank in the boat has been cleaned and the oil has been filtered. Have not tested as of yet how fast the motor tank fills with the manual switch. My testing plan will be to start with the tank on the motor empty and test all three switches as I fill the tank with the manual switch. That should tell if that switch is good. Then I will check to see it the switch in the boat oil tank is OK. Last will be checking all wiring from switches to the computer. Just waiting for some warmer weather!!! It is great to hear what others have to say also, they have given me some good ideas.