All sorted. Poor negative connection.

Now seemlessly, I have moved on to another problem.

Engine starts but when key is released the engine is cut.

Been at it all day with nothing to show for it, except a suspicion that it may be something to do with the ignition switch in that the shut off is very much the same as what happens when the 'kill switch' operates. On the point of buying a replacement

smudge wrote: It is unlikely the 'flash bang' damaged the trim. There are some sensitive electronics on outboards and trim relays aren't one of them. Can you post a pic of the electrical schematics? I was a sparky in an earlier life. I may be able to help.

Thanks for your reply.

I have 2000 Johnson 115hp Ocean Pro with 450hrs on it.

I was running a battery test (twin battery system) and while reconnecting the negative lead' I lost grip of the socket wrench which touched the pos terminal 'Flash Bang'.

I checked the fuses on the twin batt systen which were all OK. I switch on the main power and checked the instrument, GPS VHF etc. All good.

However, when I tried the trim up switch, nothing.

I took the engine cover off and found only 1 fuse. It was OK.

I tested for power at the battery/boat connection. OK 12.7v indicated.

After that I just poked and proded looking for another 'live' or fuse. There was none (that I could find).

I did though note that when I pressed the 'up' trim switch a buzzing sound came from one the two black cube shaped device (I don't know what they are) seated at the front left of the engine behind the air scoop for the carbs.

If I pressed the trim down button there was a similar buzzing but different pitch.

I don't know if this is significant or just normal.

Is anybody out there who can point me in the right direction for solving the no power before I take to a marine electrician.

Thanks