Electric Dometic awning is erratic

[Merlinmurph]

We have a fairly large electric Dometic awning (14 feet?) that is working erratically. The button is just inside the door, and when I press it, sometimes the awning will work - and sometimes it doesn't. I will always hear a 'click' from the awning when I push the button, but it just doesn't move. The awning will do this in both directions - extend and retract. With enough button pushes, I can eventually extend it, but then I have to retract it back, and that takes a number of tries.

The TT is a 2014 model, so there is a bit of age involved.

I'm guessing there is some type of electrical issue, like maybe the motor itself is bad or maybe it's not getting enough power?? I had some electrical issues two years ago because the connections on the trailer frame (breakers actually) were all rotted out and I replaced them. Our big slide and the power winch didn't work well and replacing those breakers fixed it. I'm wondering if this could be a similar issue. If so, how can I test it?

Do the motors on these awnings fail? Hey, anything can fail!

Just curious if anybody else has had this experience.

Thanks,
Murph

 

[John From Detroit]

On the front arem is a flat 2 connector if I am not mistaken near the roller..> (Like the flat 4 trailer but only two leads) See if you can sneak a small light (12 volt non-LED) into this fitting so you can see it when you push the button.. If light works but no motion it's the motor. If not the control board,.

Note use the smallest wattage lamp you can find.. The controls sense motor current and this will add to that.

 

[Kirk]

It could easily be that the switch has become burned from use, which is a normal aging. That could be checked by pulling it out, disconnecting the switch and then checking the closed switch with an ohm meter. If the meter reads more than 2-3 ohms and if it changes up into the 30–50-ohm range at times, you need to replace the switch. Switches do wear out with use.

 

[Merlinmurph]

Thanks for the input, folks.

I did some research and found one instance in which the same behavior was caused by a faulty motor. I bet a bad switch could cause the same behavior. Let me try some tests.

I also found that there are two potential motors for the awning and I'm going to ask Dometic if they could tell me exactly which motor I have if I give them the exact model number, serial number, and other info on the awning.

Thanks again,
Murph

 

[emiddleb]

A quick thing to try - get a can of silicon spray and lube the heck out of all the pivots/joints/rollers. Awnings collect a lot of dust and dirt and it doesn't take much friction to overwhelm the motors. I had one that was starting to hesitate on retraction, spraying solved the issue and is now part of my Spring checklist. First time spray enough to drip and flush any potential dirt out of the joints.

 

[Kirk]

I bet a bad switch could cause the same behavior.

You would win that bet. If you have a jumper wire you could also test it by connecting it across the switch terminals to see if the motor still hesitates. Based on my career of electrical service I would consider the switch the more likely cause and it also would cost less and be less work to replace.

 

[Merlinmurph]

Went out to the trailer today to maybe do some testing. Of course, the awning worked perfectly. I moved it in and out a lot and never got a hiccup. Kinda hard to test it when it works. Today was a dry, sunny day. The other day when it was intermittent, there had been rain and it was wet out.

I took a look at the switch anyway to see what I would do if failed and I came away unsure. Keep in mind, I know very little about electricity and these switches. I can do extremely basic stuff - maybe.

The switch has 4 wires, 3 on one side and one in the middle on the other side. Push the top of the button to EXTEND and push the bottom to RETRACT.

EXTEND
R/W------\
<---W<---P/W ]-------->
W--------/
RETRACT

R/W = RED/WHITE
P/W = PURPLE/WHITE
W = WHITE



The R/W and the W wire on the bottom form one pair of wires
The P/W and the W wire next to it form another pair.
Both pairs of wires go somewhere I can't see.
Ultimately, 2 wires lead to the motor.

Just for curiosity sake if I were to use a jumper to test the switch, how would I do it? I have no idea how this switch works.

Regardless, I'm guessing the switch is OK, leaving two possibilities.
- the connector connecting the motor wires to the wire from the trailer
- the motor

Assuming that maybe the awning fails in wet conditions, the connector is somewhat exposed, sitting in a channel in the extending arm of the awning and it looks like it. That is, it's not shiny and new looking. Maybe I'll try disconnecting it, clean the connectors and protect it with tape or something.

Then, there's the motor. Some good news is that I wrote a note to Dometic service last night asking if there could possibly be two different motors for this model like I had read somewhere. I got a reply at 7:45 this morning (!) saying that there is only one motor and they gave me the part number.

FWIW, I also lubed up all the pivots with silicone spray.

I have about two weeks before we leave on a 3-week trip. Sure would be nice to have an awning....

Thanks again,
Murph

 

[John From Detroit]

Three terminals Jumper arrange them TOP/Middle/Bottom (Does not matter for this post which is on top.

Top to middle moves one way Bottom to middle the other.

Possibility the wind sensor is the issue. Dometic uses a couple of different sensors.

One type of sensor there is a small toggle switch on the left of the big control box..
Toggle it if the problem returns and try moving. Return the switch to normal after.

 

[Kirk]

Keep in mind, I know very little about electricity and these switches.

Possibly some pictures of the switch might help as I'm not sure what the drawing means. A multimeter would also help as you could check voltages and resistance through the switch contacts with one. I am guessing that you don't have one. In my 40+ years of electromechanical service work, I have seen far more switches fail than motors and if your plan is to just start changing parts, the switch will probably cost less than a motor. If you wish to trouble shoot it, I can probably help.

 

[Merlinmurph]

Ha! I actually do have a decent multimeter and use it so little that I have to take the instruction book out every time. But it has helped me out every once in awhile at home and in the trailer.

I tried taking a picture, but it was hard taking one with the limited space behind the panel. See if this works. The left is the top of the switch (EXTEND) and the right is the bottom (RETRACT). You can see the four terminals - 3 on the right side and one on the left - and they have the colors described above.

One issue is that, right now, the awning is working fine.......

Thx for the offer. I'm just curious how to test it and learn something.

 

[John From Detroit]

If the switch is lighted odds are rhe left is for the light. I stress "Odds"

 

[Kirk]

I found a lot of awning switches with 4 connection pins on Amazon but none that are configured like the one that you have. When you describe "pairs" of wires, do you mean that they go to different locations, two in each direction?

I will assume that the switch is one that is spring returned to center and then pressed one way to extend and the other way to retract? The awning has a 12V, direct current motor and the switch supplies power to one lead and return on the other to extend the awning and to retract the power and return sides are reversed. With the switch in the center, no power should be applied. You can determine what lead has power when the awning is sitting still by measuring between the chassis ground of your RV and each pin to see which has 12V.

Here is a simple diagram of how the connections work.

 

[Merlinmurph]

First, I just noticed that my ASCII drawing of the switch above didn't render correctly. No wonder it made no sense.

When you describe "pairs" of wires, do you mean that they go to different locations, two in each direction?
Two wires on the terminals end up as one joined pair. Said another way, there are two pairs of wires, and each pair is split such that there are four wires to four terminals.
Looking at the picture, remembering that the left side in the pic is the top of the switch.:
The R/W wire on the left and the W wire on the right form a pair
The P/W wire in the middle and the W wire behind it form a pair

I will assume that the switch is one that is spring returned to center and then pressed one way to extend and the other way to retract?
Yes, correct.

I'm leaving for a few days and will get back to this when I get back.

Thanks again.

 

[Kirk]

Just ignore the part about fuses in the drawings that I posted as I borrowed the two drawings because they explain what the switch is doing. In the center position, the contacts are not connected in either direction but are all open. I'm still not sure exactly what you mean by pairs but, two wires will go from the switch to the motor, as shown in the drawings. The other two will be one 12V and one ground. With the switch in the center position, only the 12V supply lead will have any voltage applied and the mate to it should measure near 0 ohms to the chassis. The switch then connect the 12V and ground to the two wires going to the motor, one way to extend and reversed to retract, as shown in the posted drawings. Does your awning have one of the wind sensors that can retract it if the wind comes up?
Here is a better version of the diagram. With the switch not depressed the movable contact is not closed in either direction.

 

[Merlinmurph]

First, I want to thank you for your help.

I can't do much right now because the awning is working fine. I still believe it's water-related. We have had a little rain and I tested the awning then, but it still worked fine. I might need a good downpour to make things not happen.

Just for fun, I taped the two-wire connector to prevent it from getting wet.

Anyways, I'll let you know, and thanks again.

 

[mnmnutswer]

We have a fairly large electric Dometic awning (14 feet?) that is working erratically. The button is just inside the door, and when I press it, sometimes the awning will work - and sometimes it doesn't. I will always hear a 'click' from the awning when I push the button, but it just doesn't move. The awning will do this in both directions - extend and retract. With enough button pushes, I can eventually extend it, but then I have to retract it back, and that takes a number of tries.

The TT is a 2014 model, so there is a bit of age involved.

I'm guessing there is some type of electrical issue, like maybe the motor itself is bad or maybe it's not getting enough power?? I had some electrical issues two years ago because the connections on the trailer frame (breakers actually) were all rotted out and I replaced them. Our big slide and the power winch didn't work well and replacing those breakers fixed it. I'm wondering if this could be a similar issue. If so, how can I test it?

Do the motors on these awnings fail? Hey, anything can fail!

Just curious if anybody else has had this experience.

Thanks,
Murph

First this I would replace is the switch. It’s a lot cheaper and easier.