Engine control panel problem

[Mikebat]

When I switch over to battery, the control panel for the M-25XP diesel comes on. Don't have to stick the key in. It makes the fuel pump run, which is quite annoying when I don't want to run the engine (ticktickticktickticktick), and probably not very good for the fuel pump. I do have to engage the key to start the engine though, and it runs normally otherwise. I thought it might have been the key switch shorted in the closed position, but as I mentioned I do have to turn the key to ON to start the engine, so the electrical short seems to be somewhere else.

Does this set of symptoms sound like a recognizable problem I could fix easily myself? Might need to get a diesel repair service to look at it.

 

[treilley]

It could still be the switch Mike as it has 3 terminals. One for input, one for the "on" position and one for the "start" position. If the input and the "on" are shorted, it would behave as you are describing. Anything like this is potentially very dangerous. Disconnect the switch and if that does not stop it, check the wiring all the way back to the engine and the DC panel.

 

[jkenan]

I had the same issue, and TRielley is on the mark. It was my iginition switch, and for $30 bucks I figured it was better (and safer) to replace it than to try to fix my old one. I did squirt a hefty amount of anti-corrosion spray into the switch, and continue to do it on a regular basis.

The only wiring check you need to do is make sure (when the batteries are on) you have a solid 12V coming into your panel. You could also do a continuity check on the wire leaving your ignition switch coming back to your engine.

 

[Rocinante33]

John,
Where did you buy you new switch for $30?

 

[jkenan]

West Marine, Moyer Marine, you name it (I've got the atomic 4, but a switch is a switch, and would be appropriate for diesel as well as a gasoline engine, I think...).

I just did a search on both sites, and most were in the $30-40 range, with one 'keyless' option for about $100 more.