I have found a problem with the ECU and Throttle body on our boats, I think the problem is caused by connecting the battery backwards and sending reverse polarity to ECU. It will cause the engine to start and stall. The scan tool will not connect to the ECU.
So before you connect battery look closely that you connect red to Positive(+) and black to Ground( -) .
The cost is about $2100 to fix that.
Capt Rick
