Hydraulic Slides Operation Erratic (04 Dynasty)

[adcockj]

One of my first posts on this forum...thanx in advance for any ideas.

Often when I try to bring my slides in (or out) after a day or more in camp, I might get a quarter-second response like it's going to work, then nothing. When it happens, none of the three hydraulic slide switches will work. No response whatsoever. It doesn't matter if I'm on shore power, generator, or inverter.

I can wait about 5 - 10 minutes, then try again. At some point (might be the next try, maybe a later try) they'll start responding and the slides work fine like there's nothing wrong. If I can't get them to work for awhile, I'll start the engine and turn the steering wheel back and forth...sometimes they'll work then. BTW...this problem goes both ways -- if a slide's in and I want to put it out (after sitting for a day or so), it can happen in that direction as well.

I've tried to get the problem addressed by techs, but of course, they work fine when the tech tries them. I did have them just go ahead and change out the solenoid at the pump just to make sure there's no intermittent problem with it or its connection. I went a couple of months after that without them acting up, but they're doing it again. It almost seems like there might be a circuit breaker in the line, since the problem usually starts with an initial response, then nothing, then later works like nothing's wrong.

Any thoughts on what might be causing this?

Thanx/Jerry A
04 Dynasty

[Mike Canter]

Wow Jerry that is a hard one. With all the clues you have supplied it does appear that you have a loose connection somewhere. Something we need to check is that the rear slides are hydraulic and not an electric Power Gear System. Sometime the big front units are HWH hydraulic systems and the rear are electric. My rear slides are electric on my 2004 Signature.

When the rear slides work do you hear the hydraulic pump working up forward next to the stair well? If it is all hydraulic then there is a possiblity that the HWH hydraulic pump motor has a bad solenoid on it or a loose main power connection. When the slides do not work do you hear any clicking or humming or anything when you push the switches?

How mechanically inclined are you. Do you know enough to be checking tightness of nuts of main power cables under the MH?

[adcockj]

Mike:
I have a four-slide Dynasty. Both front slides, the passenger side rear slide, and the generator slide are HWH hydraulic. The driver side rear is electric. BTW...the electric slide works fine when I'm having problems with the others, so I don't think the engine-on lockout could have anything to do with it.
When this happens, I sometimes get a very short response like it's going to work (the hydraulic pump starts to work, but less than a second), then nothing at all. Other times, I just get nothing at all. I did have the techs replace the main solenoid to the pump, and asked them to check/clean all cables/contacts up there. I don't know how well they did that.
While I do have the ability to bang around on things, I'm not big on crawling around under my motorhome. Maybe I'll have to give that a try, though, next time this happens.
I'm going to give both Monaco Tech Support and HWH a call and see what they have to say. As you suggest, one would think it's an intermittent loose connection somewhere -- the hardest thing to find!
Thanx/Jerry

[Mike Canter]

If your Dynasty is the same as mine and according to my wiring diagram it is then the 12 volt power for the hydraulic pump comes from the chassis batteries through the battery switch and comes up to the Rear Run Box in the engine compartment on the curb side. If you open that RRB op then you will see on the bottom row eight large terminals. The one that supplies 12 volts to the slide motor is the one on the far left. First shutoff both battery switches and see if that nut is tight. Turn the battery switch back on and put a 12 volt test lamp or a volt meter on that left large terminal to see if you maintain power on that terminal nut when the slide is being activated and stops. From there it goes to the Front Run Box. If I remember correctly there are three large terminals on the left side of the FRB with large red cables attached to them. One of those terminals has a wire that goes to the HWH hydraulic pump. Again with the battery switch off check and make sure all three are tight. Now with the battery switch on check all three and see that they all have voltage then check them again while somebody is trying to activate the slide. If the slide stops then see if you loose 12 volts at either one of those at the same time. You might have to try it three times once on each terminal. Since you say that moving the steering wheel sometimes makes it work again then my guess is that one of those three is loose. None of these tests require you go under the coach and we have to assum that since they replaced the relay and checked the contacts on the motor then that is OK. Let me know what happens on we can go from there.

[adcockj]

Mike: Thanx much for the troubleshooting steps. I'm traveling today, but I'll go through those steps in the next day or so.
You mention that you suspect the front connections because sometimes turning the steering wheel helps. Actually, it could still be either because I start the engine to turn the wheel, so it could be moving the rear connections as well (maybe it's the starting of the engine rather than the turning of the wheel that makes the difference).
BTW...now I see why you're so smart! Retired Navy! I'm a retired cryptologist. (That may explain why I don't like crawling around under my mh.)
Thanx again. I'll let you know what I find.
/Jerry

[Mike Canter]

Let me know what you find out. I got to remember back then. Were you an "I" brancher or let me think......"R" brancher or what? Am I correct in what I rememeber. Used to fly with a lot of them.

[Mike Canter]

Jerry, in the Forward Run Box big battery lugs. Like I said there are three of them and the best I can figure out without going over to my MH yet is that two of them hook up to the house batteries and one to the chassis battery. So if you turn off just the house battery switch then only one of those three terminal lugs will have power and that is the one you are interested in. That is all from my book and not yet proven.

[adcockj]

rgr, thanx.
I was an electronics tech (ETN) in my enlisted days (8 yrs), but my primary NEC was crypto repair. I was a cryptologic officer (retired as LCDR).
Cheers/Jerry

[Mike Canter]

Jerry, just as a warning neither of my battery switches shut off power to that connector in the Rear Run Box or any of the four large terminals in the Forward Run Box. They are live all the time. The HWH Hydraulic pump is hooked up to the upper and furthest out of those four teminal posts.

[adcockj]

A status update...
I got the slides to malfunction when I arrived at a campground, so I started looking at connections/etc. I found a couple of the leads on the 87a relays (drivers and passenger slide controller/lockout relays) to be loose, so I pushed them on solid and the slides worked. Whether that was coincidence or not, I don't yet know. Hopefully, this may do the trick.
Thanx much for the help/Jerry