Step motor problem

A friend's (BigBob70's) 88 Itasca, 28 ft, class A, P-30 chassis, Chevy 454.  Step motor operation is intermittent. Most of the time it does NOT work. I discovered multiple  problems, but nothing is fixed. First, the door switch is intermittent. We tried to clean it, but it's still intermittent. Okay, that much is simple.

But even when the switch turns on the step light below the steps, the motor will work less than 20 % of the time. So I removed the PC board with the relays. Very funky contacts. I cleaned them the best I could, put it back together and it's still intermittent, mostly does NOT work.

Can somebody tell me how that motor works? Does it get reverse polarity from the relays to change direction or does it work with ground from each wire? Does the motor run on 12 VDC? The more I was trying to make measurements while working under the RV, the more confusing it was getting.

Or better yet, is a schematic diagram available for the step motor system?

Any info. will be much appreciated.

-Don-  Reno, NV  (AA6GA)


Edit by staff: changed message icon to Topic Solved

A lot depends on the model and assuming it's a Kwikee step them go here for the manuals http://www.powergearus.com/products/steps and look under troubleshooting. Or, look these over to get a better understanding http://support.powergearus.com/techdocs/875.pdf
I also have some flowcharts I can email you, just let me know as they are too large to post here.
Most models of steps are controlled by an amp limiting setup in the control module and they are 12v. That's why it's important to keep the linkage clean and lubed so it doesn't use too many amps opening or closing or it will just shut off when it reaches it's amp draw limit no matter what position it is really in. The control module does most of the work when it comes to direction etc because of the safety's and different switches, again it depends on the model and year.
If you can disconnect the step and it moves in and out freely then the control module is probably shot but follow the flow chart to make sure you aren't missing something. Hope it helps.

Mavarick said:

A lot depends on the model and assuming it's a Kwikee step them go here for the manuals http://www.powergearus.com/products/steps and look under troubleshooting. Or, look these over to get a better understanding http://support.powergearus.com/techdocs/875.pdf
I also have some flowcharts I can email you, just let me know as they are too large to post here.
Most models of steps are controlled by an amp limiting setup in the control module and they are 12v. That's why it's important to keep the linkage clean and lubed so it doesn't use too many amps opening or closing or it will just shut off when it reaches it's amp draw limit no matter what position it is really in. The control module does most of the work when it comes to direction etc because of the safety's and different switches, again it depends on the model and year.
If you can disconnect the step and it moves in and out freely then the control module is probably shot but follow the flow chart to make sure you aren't missing something. Hope it helps.

Click to expand...

Thanks.  But  I cannot read a single word or part number on anything. It might even be best if everything is changed out, as none of this stuff looks like it's in good condition.

But here is what I can tell you about the step motor system in Bob's RV. Hopefully somebody here can ID it.

The control box has three relays, one relay (with contacts that go to the motor) is in a clear plastic removable case, the other two relays are smaller and in the open on the PC board.  This is all in a black rectangular case.  Case is  held in by four screws, under the RV, with two ground wires tied to two of the screws. One wire is green and thicker than the other, which is brown, IIRC. This control board  also has a cable going to a six pin connector.

The door switch is a cheap SPST push-in switch, not magnetic.

The motor has a two wire socket for the plug in the motor itself.

Yes, if you can send more info., I will really appreciate it!

-Don-  Reno, NV

[email protected]

Mavarick said:

it will just shut off when it reaches it's amp draw limit no matter what position it is really in.

Click to expand...

If it shuts off by reaching that limit, what resets it? I noticed some large sparks from the relays, so too much current could be causing the  intermittent problems, especially if it self-resets.  But this was even with the stair's drive disconnected (pin removed), running the motor on almost nothing.

Perhaps the motor itself is drawing too much current and causing the control board to go over it's limit causing the intermittent operation. Does that sound possible?

Like I said, it seems to me the entire system probably should be replaced. The extra high current can explain why the relay contacts looked so pitch black before some cleaning.

BTW, what would the cost be to buy the new relay board, new motor, new switch  and whatever else is needed to replace the entire  system?  Is all this stuff still available to fit this 88 Itasca?

-Don-  Reno, NV ([email protected])

DonTom said:

If it shuts off by reaching that limit, what resets it? I noticed some large sparks from the relays, so too much current could be causing the  intermittent problems, especially if it self-resets.

Click to expand...

It is most likely current limiting with a few components that limits current draw and does not trip.

Perhaps the motor itself is drawing too much current and causing the control board to go over it's limit causing the intermittent operation. Does that sound possible?

Click to expand...

That is indeed very possible, especially if the bearings are packed up with dust/dirt/dried grease/oil.

BTW, what would the cost be to buy the new relay board, new motor, new switch  and whatever else is needed to replace the entire  system?  Is all this stuff still available to fit this 88 Itasca?

Click to expand...

Unless something has changed, the manufacturer will not sell parts to DIYers.

It's probably an automotive power window motor. They develop dead spots. Ever had a power window that wouldn't go back up if you put it all the way down?
Take the old motor to a real autoparts store, find the old guy behind the counter, chances are he can figure out what car it was out of and a part number.

Bill

You have a 12V DC motor that powers the steps. The commutator on the motor may be dirty and the brushes are not maintaining good contact. Make sure the steps are turned off and then go under the coach and tap the motor with a small hammer. Make sure you are clear of the travel of the steps if you are not sure  whether or not  you have the steps turned off . If you tap the motor and the steps are not turned off the steps will deploy and you do not  want your body to be caught between the steps and the ground (don't ask me how I know this) . Tapping the motor with a hammer can sometimes (it did for me) jar the commutator connection and seat the brushes for a good connection. That may cause the motor to work and if that is the case you can consider it as a temporary fix. The motor needs replacing as you cannot dismantle it and clean the commutator. It is next to impossible to re-seat the brushes (I know this for a fact). I ended up replacing the whole assembly and found out later that the motor is a power window motor. I bought my parts thru my RV dealer but I would try Kwickee first.

http://www.powergearus.com/products/steps

One forum post said that a Ford Taurus 1986 - 1995  NAPA part # BK655-1395 $63.99 Window Motor was what he used Another said from a Lincoln.

Here is a post on the Tiffin Network Forum
http://www.tiffinrvnetwork.com/crusingator/P/P-021.pdf

Since the switch is a regular switch and not a magnetic reed relay it seems like he has an early version . There may be something in the following to help. One of the places below rebuilds some of the control boards'
This is some info I have collected over the years from various threads for Kwikee steps. Maybe there is some info that will help.

Trouble shooting chart  HERE

There is a trouble shooting guide HERE

If you need sources for motors or parts check the following:

Motor 

PARTS 1

PARTS 2

PARTS 3


________________________________________________________________
"  1) AM Equipment 402 E. Hazel St Jefferson, OR 97352, (541) 327-1546 the motor is $29 plus $7 shipping.


2) Replacement step motor at AutoZone. It's a Siemens "Window Lift Motor", part number WL43003.

3) Autozone. The brand is "Siemens"
The ID tag lists the following numbers:
59720-20
121899
4) A 1986-1995 Ford Taurus left front window lift motor matched my motor. NAPA part # BK655-1395 $63.99 I ordered my motor from Auto-Zone Manufactured by Dorman part# 742-206. This has a lifetime Warranty and was $49.99.  "

Also these guys rebuild some of the older unencapsulated circuit boards: HERE

**********************************************
New info in 2012
http://www.autozone.com/autozone/parts/Aci-Auto-Window-Lift-Motor/1995-Ford-F150-1-2-ton-P-U-2WD/_/N-j1z7uZ8ijybZ1z10l3u?itemIdentifier=972601_315519_1264_1356%2C78656

Aci Auto/Window Lift Motor

For your 1995 Ford Truck F150 1/2 ton P/U 2WD 5.0L EFI 8cyl
Enlarge Image
Part Number: 83094
****************************

On disasembly of the motor I found the plastic plugs severly lopsided due to all the years of strain, new plugs cost $8.00 at Autozone or Amazon, other than that the Autozone Ford Mark VI would have worked $ $44, but I saved myself $38
*********
Just rplaced my 25 series Kwikee step motor with a Dorman 742-277 window lift motor for a 1986 Ford Taurus driver side window lift motor. They said the Taurus had a high torqe motor which is why the number ends with 277 meaning high torqe. My steps zip in and out with this motor application. It was a special order item but only took one day for them to get it to my local AutoZone store. I also noticed AutoZone had rebuild kits for Dorman window lift gear boxes (plastic gears) in the Help section of the store.

Don, with all the responses you now have all the info I would have emailed so hopefully you can use some to identify what you have.
The next thing is to disconnect the steps from the gearbox and try moving them by hand to see if they bind in any way. If they are free then you need to check the voltage at the motor as in the flow chart. If that checks out then the current limiting in the control is probably bad, or in your case the relay's and or control module. Look at the links in the posts as they are all good info if they match to what you have.
You can always call powergear but I can't say how much help they will be. It might be worth a call to Winnie to see if they can tell you what step assy they installed. If you have the serial of the rig they might have some info.
Posting some pics might also help to identify what you have. The parts are available to replace but it will probably be harder to identify them than to get them.

Mavarick said:

Don, with all the responses you now have all the info I would have emailed so hopefully you can use some to identify what you have.
The next thing is to disconnect the steps from the gearbox and try moving them by hand to see if they bind in any way. If they are free then you need to check the voltage at the motor as in the flow chart. If that checks out then the current limiting in the control is probably bad, or in your case the relay's and or control module. Look at the links in the posts as they are all good info if they match to what you have.
You can always call powergear but I can't say how much help they will be. It might be worth a call to Winnie to see if they can tell you what step assy they installed. If you have the serial of the rig they might have some info.
Posting some pics might also help to identify what you have. The parts are available to replace but it will probably be harder to identify them than to get them.

Click to expand...

Okay, thanks anyway. I expect the motor itself is the problem because of the extra high current it seems to draw even without a load. Large sparks, much more than I would expect with 12 volts on the motor. The controller shutting down made my testing very confusing. I should have asked here before I even looked at it.

-Don-  Reno, NV

Step motor followup:

I took the old stair motor out, it was a Delco #1697345. I took the motor to Napa and they cross referenced it to a window motor #4916 Ray. They had it the next day but when I compared my old assembly to the new one there were some subtle differences, enough to where the new assembly wouldn't work the way it was. There were enough similarities however for me to use the new motor with the old housing.

After switching motors  everything worked fine...The stair now works great.. ;D

Great report, glad you got it fixed!  Thanks for checking in with the resolution.

This is what I found when mine started to work only when it wanted to. Art

That's clean when compared to the way mine looked.

The contacts in the motor were rusted, the wires going to the brushes were green etc. I was surprised it worked at all..

I also rationalized the motor was 26 years old and it was time to replace it. 

Isn't it amazing what happens when you take a motor assembly that was designed to be in a protected space (inside a car door) and hang it underneath a motorhome where it's exposed to the elements?  Throw in a little road spray if your steps are mounted behind the front tire and you're in for loads of fun.

I know I am late with this, but in case someone needs help in the future I have some input. I had a 1992 Fleetwood 26 foot flair. The electric steps went out prior to my purchase. Apparently the previous owner had activated the steps next to a pole at a gas pump and that was all she wrote. However just like the others I replaced my motor with a car window motor from Discount Auto parts approx. $40.00. I think I also got the Taurus motor. I had to dremel some parts but it worked great. For some reason the auto functions did not work any longer, but the step switch by the door was just fine. I attempted to get an OEM motor and I think it was about $200. By the way the dremel part was very easy and was a fun project for the kids and I.

Thanks Charlie.

I was thinking ppl had our motor for under a $100bucks with the controller too? both the motor and controller were bad on ours, would work when ever you  least expected it too.

Art In Mobile said:

This is what I found when mine started to work only when it wanted to. Art

Click to expand...

That's what mine looked like and the steps would not work at all, After cleaning it up, they worked fine. I ended up buying a new motor and gearbox from Amazon as a future replacement.  If you take the motor apart, be careful to retract the brushes and then during reassembly make sure you engage the brushes again.

Jack