Low voltage alarm when trim up or down

Hey guys, I have a question. I have a 2015 Nitro Z9 with a 250 proxs (1B808114) and the alarm keeps going off when I trim up or down. My first thought was that it was the battery. However, I have two starting batteries running parallel and I replaced 1 just in case and had the other checked out (2019 Battery) and it was good. I even took the plate that the trim relays mount to off and sanded/cleaned the back and connectors. As soon as I put it in the water and took off, the alarm started going off again. Not sure if my next step should be to replace the trim motor or the trim relays? Any advice?:praying:
Thanks,
Dewayne

Voltage drop test are in order first

I know you mentioned you cleaned the plate that the 3 ground wires are connected to but did you clean the front and the back of the plate connection points? Did you clean the ground wires that attached to it? By cleaning you need to brush it with a wire brush. Here is my story along with the cure below....

http://www.bbcboards.net/showthread.php?t=964857&highlight=tomloans


OK guys! Pay close attention to this post before you do anything else if you have a voltage drop due to the trim motor. Problem has been solved because of repeated attempts by Don to get it through my head. I missed a step! A very crucial step. Tonight I started doing searches for a cure for this issue (again). Here is what kept popping up....

-Common ground point on electrical plate (just left of relays): Clean and restack. Remove 3 bolts securing place and ensure the surfaces are clean/grounding well.

and again this from a different post....

-Verify ground wire connections for the trim harness (bundle of ground wires below ECU, at the back of the electrical plate) are clean, and tight- with no paint or liquid tape "leached" in between the connections.

and many other posts fROm Don.

This comment was popping up everywhere and I hadn't done it. This is where the ground wire for your trim motor is located. Bad ground here and you are done.

Took ground wires off the plate and there was a small film of corrosion at all connections.IT IS HARD TO SEE THE CORROSION - BRUSH ALL CONTACT POINTS ANYWAY. Removed the 3 bolts holding the plate against the block and there was corrosion. Took a brush to all sides of the 3 areas of where the plate connects to the block and to the 3 ground wires and where they connect. As you do this you will see white dust which is the corrosion coming off. Tightened everything back and should be good for another 10 years of this motor.

Perfect voltage now. All is well. Now I can fish in peace. In this case the problem was a bad student of Don's.

Thank you all for your help and a special thank you to both Leon for encouragement and Don for sharing all his experience here. I would have missed the spring bite if it weren't for this forum and his input.

Tom

^^^^ Good advise from Tom. :thumb up2:

I took the plate off and with a round wire brush end on my drill, brushed and cleaned each loop connector for the ground, all three bolts and I cleaned the back with a flat headed screwdriver that I could fit back there without taking off the lower cowling. I'll take it off again this weekend and go ahead and take the lower cowling off and get a better cleaning. To tell you the truth there was'nt alot of corrosion back there. I wonder if maybe one of the connectors have a break in the wires in them, also? I'll let ya know what I find. Thanks for the advice!

Here is an interesting video...

https://youtu.be/Y-ZY1S0kWUA

It is almost always a bad ground.

(LSI, lets See If) this does the trick, Sometimes it does work, many times it does not leading to repeated trips out and sometimes total failures do to this approach. Much better to nail down the first time by performing the the voltage drop test to confirm you have in fact found and corrected the issue
Remember all electrical problems start with the battery, charging system and connections, Voltage drop test are easy and very quick to perform
The problem with jumping to a known issue is that you do know if it is repaired and you go out again and it is fixed or not. Test, Dont Guess
Less than five minutes with a voltmeter with cover and you would know if those grounds are good or not. Not saying cleaning them and adding a redundant one is unwise, just test them first so you can have confidence it will fix the problem and be done with it

Quote:

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Originally Posted by lpugh

(LSI, lets See If) this does the trick, Sometimes it does work, many times it does not leading to repeated trips out and sometimes total failures do to this approach. Much better to nail down the first time by performing the the voltage drop test to confirm you have in fact found and corrected the issue
Remember all electrical problems start with the battery, charging system and connections, Voltage drop test are easy and very quick to perform
The problem with jumping to a known issue is that you do know if it is repaired and you go out again and it is fixed or not. Test, Dont Guess
Less than five minutes with a voltmeter with cover and you would know if those grounds are good or not. Not saying cleaning them and adding a redundant one is unwise, just test them first so you can have confidence it will fix the problem and be done with it

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+1 Leon! How are you doing!? Hope all is well.

Quote:

---

Originally Posted by lpugh

(LSI, lets See If) this does the trick, Sometimes it does work, many times it does not leading to repeated trips out and sometimes total failures do to this approach. Much better to nail down the first time by performing the the voltage drop test to confirm you have in fact found and corrected the issue
Remember all electrical problems start with the battery, charging system and connections, Voltage drop test are easy and very quick to perform
The problem with jumping to a known issue is that you do know if it is repaired and you go out again and it is fixed or not. Test, Dont Guess
Less than five minutes with a voltmeter with cover and you would know if those grounds are good or not. Not saying cleaning them and adding a redundant one is unwise, just test them first so you can have confidence it will fix the problem and be done with it

---

+1 Leon! How are you doing!? Hope all is well.

Great video! Thanks!

Hey Leon,
Where do I need to test for the voltage test? and what am I looking for? I've got a pretty descent voltometer but can you lead me through the process please?
Thanks,
Dewayne

You will need a mercury service manual with electrical diagrams in order to follow current paths and understand them. What you will be doing is measure voltage between various point on on circuit at a time. For instance to check the electrical plate and connection you would connect the negative lead of the voltmeter to the ground wires that go to the plate. This will require a very small pin or Pico type wire piercing tool that make a extremely small hole in the insultation of the wire (more later on this). connect the other test lead on the negative battery post, Run the motor and operate the trim while watching the voltage, The reading is voltage drop in that circuit, now connect the pos test lead to a good ground on the engine block and repeat test, all circuits can be checked for resistance this way, It must have a load applied to be valid.
In regard to wire piercing with pin, I strictly mean a very sharp tiny one, that hole needs to be as small as possible, if the wires are still in good shape it will self sealing, if any doubt at all a coat of rtv or liquid tape must be used over the test point when done. The Pico tool is pricy but very good for this.Insulation Piercing Test Clip (picoauto.com) This is only wire piercing out there that I will use, also only insert the needle as deep enough to get connection, as little damage as possible
Do not pierce those wires with power probe or test light
Polarity of the test leads are not important only the reading ignore the - If it bothers you reverse the test leads

Well, I think I just made it worse. I had already bought a replacement trim motor and reservoir from Amazon (450hrs on the motor)so I went ahead and put it on. I cleaned all of the grounding locations thoroughly including the ground for the alternator. Now it will go up and down consistently 1.5 times then it just stops. just clicks. Have to wait about 5 minutes and it works fine. now My mobile vessel view won't connect to my phone, and I am feeling completely incompetent when it comes to finding the voltage drop.I watched all the videos but it seems when I look at my motor my mind goes blank. I connected ground to ground on the battery and tested the other ground wires, but couldn't find anything. I don't know if this helps but when I would hit my trim when driving the boat, my rpm gauge would max out. I have a tournament in two weeks and dont think bps could fix it in time.Could this be a defective pump since I bought it from amazon? (Not official mercury part#)

deff could be defective

+1... one of the reasons you'll see in the Forum Announcements that we do not support products purchased from the "zon" or the "bay". :wink:

Got the Mercury trim motor ordered. Keep ya updated.