unity Retractable Step Fuse?

Kozad

New member
My electric retractable entry step suddenly stopped working without any prior concerns/trouble?

Anyone know where the fuse might be found on a 2014 Unity Murphy Bed, if there is one?

Thanks
 

SSTraveler

2014 LTV Unity Murphy Bed
This happened to me on a cold day in Feb. I picked it up at the RV repair place and they had run the coach battery completely dead, this I realized when the step wouldn't retract, the radio/cameras were bone dead also. So I took it home and plugged it up so the coach batteries would charge. After several hours of charging the steps started working again but they where sluggish. I sprayed some oil on them and the started moving well. So I chalked up my incident with the steps to dead coach batteries, bitter cold, and lubrication. I thought the steps ran off the chassis batteries but after this I am not sure. I did find two MB fuse allocation manuals which shows fuse locations for electric steps, since my problem didn't turn out to be a fuse problem I didn't research further but here are the links to the MB fuse info.

www.mbsprinterusa.com/files/manuals/2013_Mercedes_Benz_Fuse.pdf
www.mbsprinterusa.com/files/.../2015_Mercedes_Benz_Sprinter_Fuse.pdf

I would be interested in your outcome, hope this helps.
 
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Kozad

New member
I have been told there is a fuse - which may either be in the battery box or as a shared fuse in the LTV fuse panel (next to the fridge in the Murphy Bed model).

I checked both locations, found a 15amp fuse in the battery box which was fine and all fuses in the panel are also fine?

Interestingly my step light illuminates when the door is open but the step does not extend. I have booked my LTV in for service and they advised that I am getting power if the courtesy step light is still working which makes it sound like this may not be a fuse problem?

I will post an update when we find out what the problem is.
 

MarkCooperstein

2014 Unity TB
The retractable stairs on my 2014 Unity TB has failed for the second time. The first time it would make a lot of clacking noise when it retracted. LTV sent me a new electric motor which I installed and it fixed the problem. Six months later, it's failed again. It doesn't even attempt to retract, doesn't even make any electrical motor noise either. It does make a clacking noise now when it tries to extend. It eventually stops making noise. The steps are stuck in the extended position. I can't even manually push them back in even an inch. They are just stuck in the out position. I haven't contacted LTV yet as I've been busy with Spring cleanup on my farm after a very harsh winter. Anyway I'm less then thrilled with the failure of these steps.

Mark. :bash:
 

HDDrvr

2013 Unity TB
Per the instruction manual for our 2013 TB: The steps should be lubricated EACH month. I would think it is the same for other Unity models.
 

Kozad

New member
Marc

Our steps have been lubricated regularly and they were working great, then the very next day there was nothing - dead! They just did not work, not an attempt at extending at all, no noise, no nothing except the courstesy light turns on; that is why I doubted this is a fuse problem... but :idunno:
 

blue

2011 LTV Unity CB
My steps started working intermittently. I replaced the switch in the door frame and they have worked fine since.
 

hahne

2015.5 LTV Unity TB
A bolt in our retractable step just sheared off when it the step was opening today. It is so strange and frustrating since our 2015.5 Unity is only 2 months old.

I have to figure out how to disable the step, so it will not try to go back in when I start the engine. I tried pulling out the unmarked 30 amp in-line fuse in the coach battery box, but it made no difference. I have no idea what that fuse is for.
 

Kozad

New member
hahne

Sorry for the late posting on what our step problem was.

Therefore the following, albeit late, refers and might offer some assistance to you:

Was told the cotter pin may have a tendency to drop out of the clevis pin in the linkage assembly (see attached diagram item 8 & 9). The clevis pin then comes loose, backs out and binds the step in either the closed or open position. That is what happened to our unit with 3500kms on the chassis, luckily in the closed position.

I was advised to remove this clevis pin and replace it with a stainless steel 2" x 1/4" bolt with a locking nut (photo attached) the motor would work once again without any issues. (Note: I was then told by my service department not to use a Stainless Steel bolt because there would be incompatibility issues causing corrosion?).

I took ours Unity to the dealership service, and they replaced the two pins and not with the bolt and locking nut, even though they told me they had used a bolt and locking nut?

When I was in Winkler last month with my Unity, I spoke with LTV's service department and they said not to put a bolt in but just use another clevis pin and cotter pin:thinking:)

So you may wish to check your step to see if there is an issue. Apparently if you pull the fuse for the step when the step is half way extended (note: fuse is located in the battery compartment in the U24MB) one is then able to gain access and replace the problematic clevis pin and cotter pin before it comes loose and jams?

I just took my Unity to the service experts to deal with the problem; this was covered by LTV under warranty :2cents:

Thanks also to NWBoater who assisted in providing me with some of this information and provided the photo of the bolt & clevis pin.
 

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Eastbayview

2012 Unity MB
hahne

Sorry for the late posting on what our step problem was.

Therefore the following, albeit late, refers and might offer some assistance to you:

Was told the cotter pin may have a tendency to drop out of the clevis pin in the linkage assembly (see attached diagram item 8 & 9). The clevis pin then comes loose, backs out and binds the step in either the closed or open position. That is what happened to our unit with 3500kms on the chassis, luckily in the closed position.

I was advised to remove this clevis pin and replace it with a stainless steel 2" x 1/4" bolt with a locking nut (photo attached) the motor would work once again without any issues. (Note: I was then told by my service department not to use a Stainless Steel bolt because there would be incompatibility issues causing corrosion?).

I took ours Unity to the dealership service, and they replaced the two pins and not with the bolt and locking nut, even though they told me they had used a bolt and locking nut?

When I was in Winkler last month with my Unity, I spoke with LTV's service department and they said not to put a bolt in but just use another clevis pin and cotter pin:thinking:)

So you may wish to check your step to see if there is an issue. Apparently if you pull the fuse for the step when the step is half way extended (note: fuse is located in the battery compartment in the U24MB) one is then able to gain access and replace the problematic clevis pin and cotter pin before it comes loose and jams?

I just took my Unity to the service experts to deal with the problem; this was covered by LTV under warranty :2cents:

Thanks also to NWBoater who assisted in providing me with some of this information and provided the photo of the bolt & clevis pin.
I had the same issue with the original cotter pin falling out. I just replaced it with a larger size cotter pin that just fits the hole in the clevis pin. This solved the problem.
The original pin is small and won't last.
 

Jeff Treiber

2015 Unity TB
My steps just stopped working. I've got power to steps (fuse in battery compartment good, courtesy light on step on), clevis pin intact, door switch still has a magnet in it. What am I missing?
 

SSTraveler

2014 LTV Unity Murphy Bed
Mine stopped a few days ago while driving and then later worked again so I oiled the hinges and haven't had any problems since. Mine have stopped a couple of times and I oil them. I think these steps really require regular oiling on the monthly interval as recommended in the manual, at least that has been my experience. I use spray wd-40, white lithium grease, silicone whatever I have handy.
 

nwboater

New member
Look underneath. My guess is the Clovis pin has broken or come out of one end causing the mechanism to bind and jam. Look for my earlier posting, or by KOZAD, for the fix.
 

MarkCooperstein

2014 Unity TB
Remember theres actually two power sources, one that drives the stair, the other comes from the ignition switch and it's only purpose is to let the stair know when the ignition has been started so it will auto retract. You might have only checked that power, and the main 12V that drives stair is out.
 

MarkCooperstein

2014 Unity TB
I would also go to the Kwikee website and download the manual. It will tell you the wiring color code. I must warn you however, if you work on the step yourself, be very careful! If it should activate while you're working on it, it will cause serious bodily harm if you get caught in the mechanism if it activates! I know, because it almost got me!

I've had my steps fail twice in one year. The first time they sent me a new motor, the second time they sent me the whole step unit to replace. It wasn't easy installing it upside down!

From my memory..you should have a 12V wire coming from the ignition switch, a 12V wire that comes from the coach battery, and one or two wires coming from door switch and finally a green wire which is ground.

Mark
 
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Jeff Treiber

2015 Unity TB
You guys had me all pumped, so back into the fray I went. Here's the latest. All fuses good (Mercedes fuse #10 well marked by LTV). Clevis pin intact and not jammed. Re-lubricated and rubber hammered it a bit to be sure nothing was binding. Shorted the door jamb switch and heard the actuator clicking, ditto when I opened and closed the door. If anyone has another idea, fire away. P.S. and probably unrelated - backup camera stopped working too, Mercedes fuse is good...
 

ewdmld

2014 Unity TB
I had an intermittent problem with the stairs not extending when the door is opened. I used a magnet to trip the switch in the door jamb and could hear the click when power went to the relay under the step, but the step did not move. My solution was to hit the relay on the front edge of the stair/motor assembly until the relay flipped and the stair opened. Used a large rubber mallet and it has been fine since. Not sure if it's a weak relay or if it just gets stuck, but you could hear it trying to work and it just needed a little help.
 

Jeff Treiber

2015 Unity TB
Gave it quite a few raps while tripping the switch, no luck. Motor was hot to the touch, so I pulled the power connector to let it cool down, then I'll try again. BTW - where is the chassis fuse for this thing? The MB fuse is for the ignition override, as Mark noted. I pulled the 20 amp fuse in the battery compartment, but the power stayed on to the steps. I don't see any LTV fuses labeled for the steps?
 

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