wont lift- need help troubleshooting

[hilltool]

So

The other day I was lifting the trailer and she just stopped half way up. Battery good (at 13-to 12.8 v). Checked connections and seemed good. There is a barely perceptible "click" when I push switch- but other than that nada.

Came here and read some old posts. Went ahead and replaced both 12v 30 amp breakers. nothing. I s there a way to bypass ----i dont know what. I did try the jumper battery thing of hooking to both posts of one of the breakers before I replaced them . no good result . Im just a bit perplexed that it quit in the middle of raising. Im stuck where to look next other than disconnecting all battery connections (two group 24 batteries in parallel) . I DO have 12volt in the the trailer. Ive had some bad connections with the switch wires before but they look ok now and the switch IS doing somethig. The trailer will lower- so Im thinking the cellenoid is functioning (?). Ideas appreciated.

Rick

 

[JackandJanet]

Rick, how's the hydraulic fluid level? If it's low, the ram won't have anything to push against it at a certain point.

Do you have the manual lift option? If so, will it lift the top more than the hydraulic system?

And finally, is there anything "catching" the top, which could be "jamming" it on the way up.

I have to confess a boo-boo I did a couple days ago, when I lowered my top. I had checked inside and out for anything that should not be there before lowering, but, in looking at the outside of the trailer, I overlooked a step stool I had that happened to be under the awning bracket. It wasn't on the trailer, so I just didn't see it. Well, as the top went down, suddenly, if kinda stopped moving right and made a funny sound. Quickly, I reversed the lift switch and raised the top and then spent about 5 minutes not finding the problem until I SUDDENLY saw the step stool!

I would not think an electrical problem would cause the top to stop lifting partway up. I don't even think a hydraulic leak around seals or in the lowering valve would do that.

Edit: I just re-read your post - are you saying the pump motor stops when this happens? If so, can you put a voltmeter on its terminals to see if it's still getting power at that point? (Do this while someone else is operating the lift switch.)

- Jack

 

[hilltool]

Jack, yes. I was raising the top and the motor quit. So, when I now push the up part of the toggle switch I get a small click. That’s it. Almost sounds like the click is coming towards the rear but I’ve got hearing aides so who knows. But no motor. There is 12.9 volts ay battery terminals and at selenoid. Lights in trailer when I check that. Almost sounds like a bad connection but it’s weird it cut out in the middle of the lift. Bad switch? Where do I place the leads on the multi meter on the pump motor? At the selenoid? Haven’t checked when switch is being pushed.

 

[JackandJanet]

There SHOULD be a +12V input from the solenoid to the motor, and then there should be a ground wire from the motor to ground. You should test for the full 12+V across these two points. This will let you know if the solenoid is passing battery current directly to the motor, which it should be doing if the solenoid is good. If that voltage cuts off, the solenoid has stopped passing current.

I don't understand why a solenoid should stop passing current with the top partway up though. About the only thing that should cause that is a sudden drop in battery voltage to it that causes the solenoid contacts to open.

You probably know this, but the solenoid is essentially a very heavy duty switch that can be closed and opened by a small current that passes through the lift switch. Its heavy duty switch contacts then pass the VERY high Amperage to the lift motor.

- Jack

 

[JackandJanet]

I've had a thought - possibly, the windings in the solenoid have developed a low level short circuit that causes it to draw too much power when you activate the lift switch. This kind of behavior could cause one of the 30A circuit breakers to pop during the lift cycle, which would cause the solenoid contacts to open.

Or, maybe the solenoid heats up and its electromagnet loses its "pull", which allows the contacts to open.

- Jack

 

[hilltool]

So, possibly replace solenoid? Also, just because it had created issues before, Im going to check the switch connections in the trailer and the ground. On my trailer the switch is mounted just inside the door on the outside of the back of the dinette bench. That wall keeps coming lose and moves a bit and, who knows? Why it would stop suddenly I dont know. The solenoid on mine is mounted on the motor. There is a ground coming off a small post on that . Ill see what I can mess with today though I have a couple medical appointments today and i have to get my mental energy up again as I got discouraged when replacing the breakers didnt work . I was messing the other day with one of those "jumper" batteries hooked to the posts on the breaker per a suggestion in another thread and stuff slipped and something got between the solenoid and I dont know what- but there was a brief "short" and a spark and for a brief second I thought I heard the lift motor start. Dont know- and I did not want to recreate a mistake to find out. That said, the breaker was warm so i decided just to replace them both.

It all worked a week ago when I opened the trailer to get something and did my own "boo-boo" lowering it and forgetting to do a final walk through and tore the top off the wardrobe. Still- i was able to get things straightened out enough for it to lower and one of the reasons I was bringing it home was to fix that and charge the batteries good. Thanks for the help, as always.

Ill check back.

Rick

 

[JackandJanet]

Your description of the problem really points me to the solenoid, but you don't want to just throw parts at the trailer to fix it. You need to see if battery current is getting to the lift motor, and from your description, it sounds like that is not happening. Yes, the solenoid is on top of the lift motor, but there should be two heavy duty terminals on the lift motor itself, which is where you would check for voltage.

Looking at the wiring diagram though, in the library it appears there are two heavy terminals on the motor that are just used to connect the negative battery cable to frame ground. I have not really studied mine to see if it's wired this way, That wiring diagram also shows a #4 (very heavy) wire going INTO the solenoid from the positive terminal of the battery. That makes sense, it is the input feed to the contacts. Possibly, there is then an "internal" connection from the solenoid contacts to the positive terminal of the motor.

If this is the case, I don't see how to easily check for current output from the solenoid to the motor, unless you take the solenoid OFF the motor, which would expose the positive contact you need.

I know I'm using voltage and current sort of interchangeably here, but you will be checking for voltage, which will tell you that current can flow.

- Jack

 

[hilltool]

solenoid. red cable to battery pos. little yellow wire heads back towards main cabin. negative battery cable attaches low on steel bracketet holding [ump/resevoir. And that is the ground for battery ground. I got 12.9 volts between little yellow attachment and red cable attachment with no buttons pushed. just lying in state.

 

[hilltool]

you can barely see ground but if you look hard it is tucked down in there.

 

[JackandJanet]

The yellow wire should be the lead from your Up/Down switch to the solenoid. When the switch is Up, it should provide +12V to the solenoid, causing it to close. You can test this by putting your voltmeter positive lead on it and the negative lead on the negative battery terminal. If it's getting voltage with the switch "Up", and the motor is not running, I'd say the solenoid or the motor itself is bad.

The red cable is the input to the solenoid contacts from the battery. I don't see the output, which must mean it's "internal". And yes, the black cable is the ground to the motor.

I'm puzzled you get battery voltage between the red and yellow wires. That must mean the yellow wire is "grounded", which doesn't make sense. If you probe the yellow wire and ground, do you see 0V with the lift switch "off"? You should. If the yellow wire is grounded, you could then test for this by putting your multimeter to "continuity", then one probe on the yellow wire and the other on ground (with the lift switch OFF!). If it shows continuity, then, for some reason, with the lift switch off, the yellow wire is grounded, which is not bad, but doesn't seem necessary.

I still think the solenoid is the culprit.

- Jack

 

[hilltool]

Thanks Jack. Always an education. I will continue to pursue this and see whats up. Ill be checking back. Stay safe.

Rick

 

[hilltool]

So- I stopped by the dealer this morning where I bought it. That guys said likely power issue. I said batteries were full at 12.9 he pointed out the "full" was 13.0 something and I said good point but I felt 12.9 should lift it.

Anyway- he suggested I take the positive terminal going to the solenoid off and touch it to the other side of the solenoid where there is not a cable attached . He warned there would be a spark, but if it it raised he said it means it is not the solenoid. So I did that. It raised. So, I am off to prepare to remove and likely replace all battery cables and clean contacts. Jack, do you agree with this diagnosis- that if it raised in that scenario it isn't the solenoid? One wire at a time I guess.

Thanks

rick

 

[JackandJanet]

No, I actually don't agree! !2.9V is MORE than is normally found in a fully charged wet-cell battery in its resting state. The nominal value for a new battery is 12.7V.

Now, I have to admit I am hazy on the wiring internals of a solenoid, I just know it is an electromagnet that pulls heavy duty contacts together to provide an electrical path for a very heavy current draw. A relay is another kind of switch that does this, but it doesn't pass nearly as much current. I'll refer you to this Wikipedia page: https://en.wikipedia.org/wiki/Starter_solenoid which covers everything I know about solenoids. Notice, in a car, the solenoid also physically moves the starter drive into the ring gear of the engine, to turn it. I don't know that our solenoids have to move the motor drive into the pump, but they may.

You MAY have bad cables or corroded contacts. I think a visual inspection and cleaning would confirm or deny that. It's certainly worth looking at. The connection by the red positive wire to the solenoid looks solid to me, as does the wire itself (what I can see of it). I can't really see the negative (black) cable well enough to judge its condition.

I can't help but wonder if connecting the red wire to the other terminal on the solenoid bypassed the internal switch, feeding battery current directly to the motor. If it does that, then, I'm back to a solenoid problem. Again, I don't have any idea how the solenoid is internally wired.

- Jack

 

[garyk52]

1 motor is good
2 ground for motor is good
3 bypassed solenoid motor ran
4 make sure solenoid is grounded
5 take a jumper wire from heavy red wire on motor to small terminal (yellow wire) if motor runs solenoid is good, motor doesn't run bad solenoid. (try tapping solenoid with hammer)
6 if motor ran you have a switch or wiring problem going to solenoid.

 

[JackandJanet]

Great suggestions, Gary! (Wish I'd thought of them!) Steps 4, 5 and 6 are what you need to try now, Rick. Notice that's a "jumper wire" from the red cable to the yellow terminal, not the red wire itself! The "hammer" approach can often free a stuck solenoid.

I love the intelligence and knowledge in this forum!

- Jack

 

[hilltool]

Thanks guys. I’m on it. Am in process of removing old negative battery wire from motor bracket where it is currently soaking in a good pb power blaster bath. That is the cable that grounds the whole shabang. Clarification: how do I know if solenoid is grounded? I am assuming it’s mount to the motor housing is the ground?

Did discover I have one battery reading 12.4 and one reading 12.8. Though, when reading across batteries when wired parallel I got 12.8. Damn. That means replacing them both or just running with one, I guess.

Ok. I’m sort of suspecting switch connections which I have from the beginning Because I swear the “ click” I hear is coming from switch wiring area. but they are such a pain to get to. I’ll let you all know. Check in from time to time. This is definitely going to stretch into the weekend.

Rick

 

[garyk52]

how do I know if solenoid is grounded? I am assuming it’s mount to the motor housing is the ground?

Normally yes, however I can't see the mounting bracket in your photos plus your motor case is rusty, so check for a good ground

 

[garyk52]

Just a FYI my up down switch clicks, just went out and tried it.

 

[JackandJanet]

My lifting switch clicks too. Gary's troubleshooting points will tell you if the problem is in the wiring to the yellow terminal. From your description of the problem, Rick, I don't think it is.

When you have two batteries connected in parallel, both HAVE to read the same voltage if you measure across the terminals of each. You can think of it as the high voltage battery sort of "powering" the lower voltage one, but that's not really right. It's just that the voltage has to match because they are connected together. Disconnected, so they can be measured separately, they might well read differently. A reading of 12.4V on the one battery means it is weak, but, I bet it would still raise the top on its own if you connected it to the motor. A reading of 12.4V is what you normally see on a battery at 75% charge.

Yes, you should probably get two new, same brand, same size, same mfg date batteries; but first things first - figure out what is causing the lift problem.

- Jack

 

[hilltool]

WEll- it lifts! Had to remove a battery (actually, the better battery) to get at the ground connection for the negative cable that grounds everything. So, I just went with one battery for the rest of working through Garys sequences as I figured that, at least, eliminated a couple of cables and connections from consideration. Replaced the ground cable as a i felt a little wiggle where it connected to the connector for the battery connection and I guessed it had been on there for 10 years of more. Got it all hooked back up and was getting ready to put a wire between solenoid positive connection and the yellow post on top and I thought, "Well,don't be stupid. At least see if lifts with the new cable on", and, voila, it did! So, I will now continue and replace all other cables seeing as they are all currently disconnected and I might as well. A good lesson all around especially if the culprit WAS the ground cable, seeing as the fact that the rest of the 12v system was still functioning made me eliminate that for immediate consideration . Of course, the issue could have been with one of the other connecting cables though the same rationale would/does apply. Anyway- I get to watch football tomorrow instead of playing with this issue. knock on wood.

Anyway- thanks Jack and Gary. I need to bookmark this thread as it turned into a great tutorial on trouble shooting electrical issues for lifting. Once again, this forum is much better than the dealer.

EDIT: on second thought, it doesn't makes sense. The trailer did lift when bypassing solenoid so apparently the ground cable was good enough to allow that to happen. The only other thing I can think of right now is there is a wire connecting the positive terminal on solenoid to the 30 amp breaker I replaced and when I re-connected the positive cable from the battery to solenoid that wire connects in the same place. I assume though that breaker is how positive current makes it to all other places in the trailer that needs it. so i was thinking a better connection there when I reattached stuff might have made a difference. But, still, I was always getting 12v in the cabin through all of this. This is why i really dislike electrical problems.

Rick