2004 Mercury 115 trim not working

[firedog80]

I have a 2004 Mercury 2 stroke 115hp. After a thunderstorm the other day went out and the engine was trimmed all the way up with the pump still running and would not go back down.

I recharged the battery and switched around the relays, but changed nothing. I lowered the engine and reconnected the power wire and the engine goes right back up. Only stops if you hit the down button, but soon as you let go it will keep going up.

Can anybody give me some clues on what to check to figure out what I need to fix this problem?

 

[RRitt]

Re: 2004 Mercury 115 trim not working

disconnect motor from wiring and hot wire the motor. if everything works fine then it is in your wiring. I would guess a short on control lead from console to relays (including both switch and wiring as suspects)

 

[Texasmark]

Re: 2004 Mercury 115 trim not working

My guess would be the switch was hit. Lots of unknowns but the switch is probably on the shift handle putting it up in the air where lightening could get to it. So what was the path for the lightening? Where was the ground? What else did it tear up? Why? On and on.....

A carbon path in the switch from power to the up direction could do it. When you pushed the button down you made a solid electrical contact and that current may have exceeded the current to the up and you could drive it down. Then as soon as you released it the low current path to up raised it back up.

Go to the engine and disconnect the blue/white stripe and green/white strip wires which are external to the remote cable which is plugged into the engine electrical connector. They are at the end of the remote cable near the plug and tie wrapped to it. There will be two more wires external with these (total of 4), a tan for remote over temp indicator, and a brown/white for a trim dash indicator.

If this solves the problem either the switch is bad on the shifter, or a wire is shorted in the harness from the remote to the engine. An ohmmeter testing between the center pin and each side of the switch will verify continuity that isn't supposed to be. Then is it the switch (probably) or the wiring. Otherwise you have a relay problem. But you switched relays so that eliminates that.

So, it looks like you have 2 answers with the same result. Great. No confusion.

Mark

 

[RRitt]

Re: 2004 Mercury 115 trim not working

i was thinking water short from rain. aren't 2004 EFI engines? I think if an EFI boat got hit by lightning then it might not be worth fixing due to cost of electronics.