trim sender wireing

[knightowl]

Can anyone tell me where the 4 wires go that come in from the outdrive sensors to inside the boat? All i have is 4 wires sticking out bare. My trim shows all the way up every time i start the boat.

Thanks for the tips.

 

[achris]

Re: trim sender wireing

Assuming it's a Mercruiser, otherwise all bets are off.

One pair is the trim limit switch, which should be connected to the trim pump harness. The other pair is the trim gauge sender, and one lead should be connected to ground, the other to the brown/white wire in the engine harness at the back of the engine...

Chris..

 

[knightowl]

Re: trim sender wireing

thanks for the reply.

could you be more specific by engine harness? Possible for pictures or drawings?

79 350 260hp.

 

[Don S]

Re: trim sender wireing

thanks for the reply.

could you be more specific by engine harness? Possible for pictures or drawings?

79 350 260hp.

At this point, there is no way to be specific until we know exactly what outdrive you have.

 

[knightowl]

Re: trim sender wireing

Used to have mercruiser alpha one. Had to replace with SE106 drive.

Let me know if there is any diagrams existing. Thanks.

 

[Don S]

Re: trim sender wireing

Here's a link to the OEM service manual. It will have diagrams in it.
Click Here

 

[knightowl]

Re: trim sender wireing

Your awesome Don! Let me take a peak at the manual and hopefully i will find what i need.

 

[knightowl]

Re: trim sender wireing

Ok, according to this picture, this is the closest system to mine.

However, in this picture, it shows only 1 trim unit switch. I have two total. (one on each side of the drive). That is why i end up with 4 wires.

Are these wires suppose to be spliced together (per each side) and then headed to the trim control like in image? Or is the trim unit switch suppose to splice together with the other trim unit (per wire) and then go to the power trim control?

 

[achris]

Re: trim sender wireing

Re-read my first post. You have a limit switch and a gauge sender. That drawing is for the limit switch and is connected to the pump harness. Go to the wiring diagram of the ENGINE manual (you'll need to tell us what engine you have, and its year) and look for the gauge sender... Like this....

Chris..............

 

[knightowl]

Re: trim sender wireing

79 350 260hp.

like i mentioned in the top, its a 1979 mercruiser 350 260 hp.

 

[achris]

Re: trim sender wireing

like i mentioned in the top, its a 1979 mercruiser 350 260 hp.

Sorry, missed it. The drawing above should still right for your engine...

Chris.......

 

[knightowl]

Re: trim sender wireing

Thanks Chris. I notice on one of the switch it says "T.P" on the other it says "T.L" What does that mean?

I also spent about 2 hours trying new wires to wire up this stupid trim thing. (before i saw your chart).

Ive tried many combo's connections with negative and positive to the sender on to the gauge with new wireing and nothing seems to work. This is a 2nd year nightmare with this dumb trim gauge thing. I have two of the switches on outdrive which makes them a heck of a time to find out which one is the switch and which one is a sender. How come manuals only show one switch? There are 4 wires coming inside the boat from the outdrive not two. I am one puzzled man right now.

 

[stonyloam]

Re: trim sender wireing

I notice on one of the switch it says "T.P" on the other it says "T.L" What does that mean?

The one on the port side is the trim limit (TL) switch and the one on the starboard is the trim position sensor (TP).

 

[stonyloam]

Re: trim sender wireing

I have two of the switches on outdrive which makes them a heck of a time to find out which one is the switch and which one is a sender. How come manuals only show one switch?

Because the trim limit switch is the only real "switch", that controls the upper limit of the trim of the outdrive. The other "switch" is just a rheostat type sensor that goes to the trim gauge.

 

[stonyloam]

Re: trim sender wireing

OK let's take a step back here. Does your trim up work? Does your trailer switch work? If the trim up works, someone has bypassed the trim limit switch. Look for a terminal back in the stern that has 2 blue/white wires in it. That is your trim limit switch connector. Also look for a purple/white wire back there. That is your power from the trim switch. Has someone jumpered the two connectors together? Next lets follow the wires, follow the two sets of black wires back to the transom shield, if you can see where they come through the pair on the port side should be the trim limit wires. It's not so bad, should be able to figure it out, first the TL, then the TP maybe

 

[knightowl]

Re: trim sender wireing

My up and down does work. I have no idea how to manage to by pass it since 4 wires are sticking out in board but the trim still works fine.

I will go through your steps and check it out. One thing is for sure, i have like 4 different purple/white line wires.


Also what do you mean by TRAILER Switch?

 

[Bt Doctur]

Re: trim sender wireing

On most control boxes there is a trim switch and trailer switch, some have the dash mounted trailer button, some also have 1 button on the left side of the handel (trim in/out) and a second button on the right side of the handel.(trailer) pressing both is the trailer option.pages 5A-60 and 5A-61 http://www.boatfix.com/merc/Servmanl/14/14a5.pdf

 

[knightowl]

Re: trim sender wireing

i have the 3 button controller. 5A-60

 

[Bt Doctur]

Re: trim sender wireing

It`s supposed to work like this, press the bottom button to lower the drive, press the middle button for trim, outdrive should stop partway up(trim limit), pressing both the middle and top at the same time give you trailer mode to raise it all the way up.
If not, somethings been bypassed ,most likely the trim limit switch.This would allow the drive to come all the way up with the trim button.

 

[stonyloam]

Re: trim sender wireing

My up and down does work. I have no idea how to manage to by pass it since 4 wires are sticking out in board but the trim still works fine.

I will go through your steps and check it out. One thing is for sure, i have like 4 different purple/white line wires.


Also what do you mean by TRAILER Switch?

If your trim up (the middle button) works, someone has already bypassed the trim limit switch.

In the stern there should still be a connector with two blue/white wires coming out of it. the way you normally bypass the trim limit is to jumper between the p/w wire and the b/w connector. Sounds like it is kinda messed up.