Honda BF130 no MIL light

MIL light not working at all. I bench test it directly with 12v and buld is working but no signal at all from computer. Any ideas for troubleshooting ??

When you turn the key on it should blink and stay off. if it stays on there is a short some where or a faulty sensor plugin in the DLC and see if it flashes a code .

Workshop manual with a wiring diagram would be the first step. You more than likely have a wiring fault in the 3 wire harness from the engine to the dash. Just to give you a bit of a heads up, disconnect the 3 pin harness at the indicator light. The Blue/yel should have a constant 12v with ignition on. If not, go to the 3 pin harness on the engine side and see if the same wire has 12V. If not, check at the alternator,same wire, if not then check the same coming out of the main relay. I am guessing this wire has a break or corroded terminal somewhere since it feeds both the alternator and check eng light. I am assuming here the engine runs normally?

Thanks for your response, there is no voltage at all at the 3 pin on the MIL side bulb. Its a new boat for me and I didnt know the MIL light should have turn on for 2 seconds when I start the engine. I realize this because I took a hard landing and the engine when down to 2500 RPM. It was a 3 hour trip and after a few hours on our way the engine when up again. And is doing this every time I start the engine. It stay in low RPM for the first 15 to 30 minutes and then rev up. When I try to follow manual to read codes I realize then the MIL light wasnt working. So the first thing I want to do is fix the MIL light to see if I have an error code.

Ok, asper maintenance manual only 3 posible reasons. MIL bulb or bad wire, if those are good then problem will be ECU. Unfortunatley for me I cant continue troubleshooting until next thursday.