Trim Sensor Wiring

[hippovet]

I have a 2008 Mercury 40 hp EFI 3 cylinder 4 stroke. I bought it used (very low hours) and added a Smartcraft 1000 tachometer and electric trim/tilt. I recently purchased a Smartcraft compatible trim sensor and installed it today. Unfortunately I can’t figure out the wiring. The sensor has three wires, black, yellow and blue. The instructions say to connect them to the same color leads from the Smartcraft internal harness. BUT, there are only two available leads in the engine compartment and they are brown/white and purple.

Actually, I looked again and there is a hidden bundle of additional open connectors at the front of the engine. There are two yellows, which are connected together by a yellow jumper, two blacks, and a couple other colors. No blue wire. I don’t think that these are what I’m looking for.

Everything seems to work fine with the tachometer and trim/tilt that I installed.

I’ve attached an image of the wires from the sensor and the free wires on the engine side.

Any ideas?

Thanks

 

[Chris1956]

The trim sensor is likely brown/white at the engine. The gauge will also need power and ground. On the engine they are purple and black, respectively. Not sure about Smartcraft wiring colors.

Your motor does have a trim sensor? Not all did.

 

[hippovet]

The trim sensor is likely brown/white at the engine. The gauge will also need power and ground. On the engine they are purple and black, respectively. Not sure about Smartcraft wiring colors.

Your motor does have a trim sensor? Not all did.

Chris1956,

Thanks for your reply. I just added the trim sensor. I also added the Smartcraft gauge, which has power and ground. Apparently my engine does not have all the Smartcraft wiring.

I think I’ll connect the yellow wire from the sensor to the brown/white wire at the engine and the black wire from the sensor to a black wire at the engine for a ground. Can I safely assume that all available black wires are ground?I’ll leave the blue wire from the sensor disconnected. We’ll see if that works.

Should I connect the blue wire from the sensor to the purple wire at the engine? Does the sensor need power? I read something about the purple wire being part of a trim limit indicator or something like that.

Thanks again

 

[hippovet]

Chris1956,

Thanks for your reply. I just added the trim sensor. I also added the Smartcraft gauge, which has power and ground. Apparently my engine does not have all the Smartcraft wiring.

I think I’ll connect the yellow wire from the sensor to the brown/white wire at the engine and the black wire from the sensor to a black wire at the engine for a ground. Can I safely assume that all available black wires are ground?I’ll leave the blue wire from the sensor disconnected. We’ll see if that works.

Should I connect the blue wire from the sensor to the purple wire at the engine? Does the sensor need power? I read something about the purple wire being part of a trim limit indicator or something like that.

Thanks again

I did what I said I’d try (yellow to brown/white & black to black) and nothing happened.

The Smartcraft gauge is digital. Because it seems to work for RPM, battery charge, engine temperature, oil pressure, hours, etc., I assume it’ll also work for trim if wired properly. Trim is one of the modes displayed on the gauge. It seems that my engine is mostly wired for Smartcraft but it doesn’t have the yellow, blue, and black wires that the installation instructions for the trim sensor (a Mercury Marine product) say should be there. The engine does have brown/white and purple wires available.

I don’t want to randomly connect wires and hope for the best. The only things I’m pretty sure of is that the brown/white engine wire is trim and the black sensor wire is ground. I’m hoping that someone who is familiar with these systems can straighten me out. I’m also going to try to contact Mercury Marine for help.

Thanks

 

[hippovet]

I did what I said I’d try (yellow to brown/white & black to black) and nothing happened.

The Smartcraft gauge is digital. Because it seems to work for RPM, battery charge, engine temperature, oil pressure, hours, etc., I assume it’ll also work for trim if wired properly. Trim is one of the modes displayed on the gauge. It seems that my engine is mostly wired for Smartcraft but it doesn’t have the yellow, blue, and black wires that the installation instructions for the trim sensor (a Mercury Marine product) say should be there. The engine does have brown/white and purple wires available.

I don’t want to randomly connect wires and hope for the best. The only things I’m pretty sure of is that the brown/white engine wire is trim and the black sensor wire is ground. I’m hoping that someone who is familiar with these systems can straighten me out. I’m also going to try to contact Mercury Marine for help.

Thanks

I heard back from Mercury Marine. They confirmed what I had already figured out- that my engine, while Smartcraft “compatible,” will not accept a digital trim sender. I will need to use an analog sender and gauge.