Gremlins in the trim!

[DBrimer]

Hey guys,

I'm having trouble with the trim on a 94 bayliner capri 1800 with a Force 120 outboard. I replaced the trim motor last year and when I put her to bed last fall, all was well. I was getting her ready the other day and tried the trim out - she'll go up just fine, but all I get is an electronic "click" sound from the back of the boat when I push the button up at the throttle lever. So in my troubleshooting, here's what I've found so far:

- I've put a meter on it and I get 12V DC through the outbound wire on both the up and down relays when I push the corresponding buttons.
- I have a continuity tone when I tap both leads going to the pump motor.
- If I switch the up and down leads from the motor with their corresponding relays, the motor will go down just fine, but will not go up - just a click...so I know the motor is good.
- I'm assuming if I get 12V out of each relay when I push a button, the relays are good?

I'm stuck at this point, staring at a length of wire with some demon in it lol. Any ideas? Thanks in advance!

Dustin

 

[wrench 3]

I don't know much about the Force trim system, but if you have a two wire trim motor and five wire relays, it's most likely the relay that's not clicking when you try the down. The inactive relay has to supply ground to the one motor wire. Both relays ground the motor wires when every thing's off. And then one relay switches it's wire to positive when it's activated.
Check the connections at the relay also.

 

[DBrimer]

Thanks Wrench. Yes you're right in that its a 2-wire trim motor and it uses two 5-wire relays. Thanks for the info, I didn't know that the two relays work in tandem, rather than one being exclusive to each movement. I hear a clicking sound when I push the down button, but seeing what you've written, I guess that could easily be one and not the other doing its thing.

I'll double check the connections at the relays. If they seem solid, is it pretty safe to assume that a bad relay is to blame and (fingers crossed) that the fix would just be to replace the relay?

 

[wrench 3]

Just to clarify, only one relay activates (clicks) in each direction. They're a single pole double throw relay. In other words, when the relay is inactive (off) it connects the terminal #30 from the motor to the grounded terminal #87a. When the relay is activated it switches the motor terminal #30 to the positive terminal #87 from the battery.

 

[DBrimer]

Oooh, well that makes more sense. So then by process of elimination, I must be looking at either a bad relay or one of the blade connectors on the harness side is probably loose (either to its respective wire or as it latches onto the relay)?

Thanks again Wrench.

 

[wrench 3]

It sounds like you have a pretty good handle on things.
Good luck.