Mercruiser trailer button missing

[bashr52]

While going through my spring boat prep I've been finding more and more things done to the boat during its lifetime (wiring issues, missing parts, etc). There has always been a bracket mounted on my dash that I had no idea what it was for. Last night while correcting the missing trim limit sensors I noticed that the system had been wired together such that no trailer button was needed, there was nothing limiting the trim system from lifting all the way up. There is a wire in the trim control harness that is just dangling under the dash which I has chased down as going to the missing trailer button. A quick ebay search found the missing button, which has the same bracket mounted to it as what is still on my dash.

How is this trailer button supposed to work? It looks like just a momentary 2 wire switch. Short of buying this one, I'm wondering if I can just mount a momentary switch in the existing bracket, and wire it in as normal. One wire goes to the purple wire under my dash, but where does the other go? Does the trailer button send a ground or voltage system to the trim pump to allow the drive to tilt to trailer position?

 

[sogood]

That's exactly the same button that was on my boat and was seized solid. I replaced it with a stainless steel momentary push button that fits snugly inside the original housing, thus maintaining the original look. I don't see any reason why you can't replace yours with a similar push button switch. Mine has just two wires, can't remember the colours but they weren't black and red as in your pic. Orange and grey come to mind. The purple under your dash may well be an ignition feed but I may be corrected on this.

​I replaced the trim and tilt button on the top of my gearshift also, as it was floating about with very poor intermittent contact. I just re-routed the wires down to the dash and used a 2 position momentary rocker switch. Up for up and Down for down. same thing I suppose.

 

[alldodge]

It bypasses the trim limit switch, so it connects to the Blue/White wire. Now if your limit is not installed, then there is no need for the trailer button

 

[bashr52]

I know which wire it needs to go to in the trim/tilt harness, just not clear on the other end. Does the trailer button ground out the circuit or put power to it?

 

[alldodge]

I know which wire it needs to go to in the trim/tilt harness, just not clear on the other end. Does the trailer button ground out the circuit or put power to it?

Transfers power from the purple/white to the blue/white

 

[bashr52]

No Title

I snapped a quick pic of the wiring today. I found a button that will work and will wire it up tomorrow. The blue/white wire is spliced into the blue wire on the trim switch, so should I just Y off the blue wire to tie it into the purple/blue of the trailer switch?

 

[alldodge]

Unless someone changed the wire there shouldn't be a solid blue wire. That said if the blue/white and purple/white wires that are in the pic connect to the trim limit on the drive, then yes connect the switch between the two. The purple/white should have power on it

 

[bashr52]

The wire harness from the trim to the switch are blue/white, purple/white, green, and red. The blue/white, green, and red wire are all connected to the trim switch, the purple/white is just hanging out there. I'm going to splice a second wire into the blue/white bundle so the trailer switch will have the purple/blue wire and purple/white wire on it, with the blue/white also running to the normal trim switch.