Lift Master Garage Door wall switch display / motion sensor controller display disappeared no back light

[sam_sam_sam]

This happened last Saturday and today I finally had time this morning before I went to work to replace two non brand capacitors

I will let you be the judge weather or not these are bad or not according to the blue ESR meter that I am using

I am comparing them to a brand new one that I installed

The display came back on and the programming was not lost which I was surprised by I would have thought that when the display went blank that so did the memory as well

I going to let it run for several days before I remount back on the wall next to the side door going into the garage and before I remount I take some pictures of the display controller

One note before I replaced both capacitors I re-hook the controller board back after about 5 minutes the back light came on only one line came back on and I do not remember exactly what it said but this was not normal so I did not leave it connected I just replaced them when researching about another issue I was having when I first started using this garage door opener I saw some reviews about this particular issue with display either no display but back light or no display and no back light and I had the no backlight and no display and the suggesting were to replace the two capacitors or get a new display controller but apparently thy keep using these off brand capacitors and don't give a shit

one capacitor is 220uf @ 35 volts 0.16 new one is 0.09 ( this I have my doubts to weather not this good or not )
second one is 100uf @ 50 volts 0.13 new one is 0.09 ( this one might be alright )

I am wondering if I should just go ahead and recap the main controller board as well or wait until something else does not work correctly again

[redwire]

The old caps look OK, I don't see a problem with them besides the unknown brand. Low ESR is only important in a SMPS I think. I will sometimes check leakage current as well.
What model Liftmaster, is this display on the two-wire bus they use? I ask because the opener supplies power to both the obstacle sensors and this display and if there is a short with the sensors or the wall display, it might cause a no or low power situation. You can measure DCV on the two-wire or try disconnecting the obstacle sensors to see if they are loading down things.
Otherwise I would look inside the opener and see how the capacitors look. I recapped a garage door opener, they are powered 24/7 and see hot weather during summer and after 10-15 years it's time.

[sam_sam_sam]

Yes it is a two wire bus and to answer your question the LED lights were on the obstacle sensors which was surprising to me which did not make sense but something else that did not make sense either was I checked the two capacitors ( on the board ) with a multi meter and one of you got the results that you would expect but other one showed a short for quite a while before the value was going up which I found really strange

This garage door opener is not that old yet but this not the only issue that I have had with it I would have thought Lift Master made better garage door opener than the experience that I have had with one I have been very disappointed with the quality of this particular garage door opener

One note it was very hot Saturday late afternoon which is when all this happened

I just hope that Lift Master did not use a switching power supply that has the bus ic chip in it because I once worked on one and this ic chip keep the switching power supply from turning on once removed it function correctly but the device did not I had to replace the switching power supply then the device started working again but I used this switching power supply that had this issue as a testing jig if the device power on but the device did function correctly and gave a power supply error I knew what the issue was

[sam_sam_sam]

Well I am not sure exactly what wrong with the garage door opener but at first the display is not working but after pushing the button several times the display screen comes back on and the temperature is reading but it is switching between “F” and “C” and if you press it a couple more times the display momentarily disappears but the backlight stays on but the garage door does not open I am being to think that there is something wrong with the bus communication the obstacle sensors LED lights are on and are not affected by the display screen or it's buttons being pushed

So what gives here any ideas to what going on here

[redwire]

Was there a thunderstorm that day?
What I would do is measure DCV on the two-wire bus and disconnect stuff to see if something is damaged and loading it down, or the opener is weak. The wall unit acts like it's starved of voltage?
It's normal the DCV moves around because there are data pulses superimposed on the DC power it provides to the wall switch and obstacle sensors.
It's a party line with 4 devices on it - wall switch, obstacle IR transmitter and IR receiver, and the opener. I don't know an easy way to isolate which one it is.

[sam_sam_sam]

Was there a thunderstorm that day? ( No )
What I would do is measure DCV on the two-wire bus and disconnect stuff to see if something is damaged and loading it down, or the opener is weak. The wall unit acts like it's starved of voltage?
It's normal the DCV moves around because there are data pulses superimposed on the DC power it provides to the wall switch and obstacle sensors.
It's a party line with 4 devices on it - wall switch, obstacle IR transmitter and IR receiver, and the opener. I don't know an easy way to isolate which one it is.

Would it be better if I just got a new garage door opener and then try to figure out exactly what is wrong with it because I know that if it is a problem with bus system it not going to be easy to figure out exactly what is wrong with it because it is interesting thing is that the remote actually works the garage door opener

Because the wall switch/display controller says again needs reprogrammed again so I am sure what going with device

[CapLeaker]

My garage door openers are now 19 years old. I replaced one bad incandescent light bulb for a LED like 3 days ago and I replaced one remote (big brick with a 9v battery) about 3 months ago after wifey hit a deer and totalled the Audi. Other than that I had nothing going on with the garage door opener and still works good.
Not sure why your opener has a temperature reading? Must be much newer than mine.

[redwire]

Would it be better if I just got a new garage door opener and then try to figure out exactly what is wrong with it because I know that if it is a problem with bus system it not going to be easy to figure out exactly what is wrong with it because it is interesting thing is that the remote actually works the garage door opener

Because the wall switch/display controller says again needs reprogrammed again so I am sure what going with device

If the wireless remote works, the opener must be communicating with the obstacle sensors. But you said some LED is on.
I would disconnect the wall switch and verify that the opener and sensors work. Then there must be a problem with the wall switch. You never gave a model number for any of this.


Liftmaster/Chamberlain openers are pretty cheap quality - tiny, brushed DC motor slow as molasses, with small plastic gears. They are not made to last. Fair bit of work to replace an entire opener system. The limit switches/screwdriver adjust is gone and you use software to set that now KKKCCCRUNCH lol. IoT and the phone app require coms with HQ, so if the server is down no remote operation that way.
I keep fixing an old beast as well.

[CapLeaker]

My openers just stop if there is too much torque on the motor opening and closing. No crunch.

[sam_sam_sam]

My openers just stop if there is too much torque on the motor opening and closing. No crunch.

This does that when it works correctly the remote controls the garage door but now I have a foreign language on the screen wall switch I think it is Spanish but I am not 100% sure of this I do not remember setting it to this particular language so I do not

[CapLeaker]

This does that when it works correctly the remote controls the garage door but now I have a foreign language on the screen wall switch I think it is Spanish but I am not 100% sure of this I do not remember setting it to this particular language so I do not

Geez, now I am getting curious. What the heck is that for a crazy @$$ garage door opener? A wall switch with a language setting? Man.. maybe I am getting too old for dat chit. I can hear redwire laughing his @$$ off. lol

[sam_sam_sam]

Geez, now I am getting curious. What the heck is that for a crazy @$$ garage door opener? A wall switch with a language setting? Man.. maybe I am getting too old for dat chit. I can hear redwire laughing his @$$ off. lol

He probably will I have found this hole episode not real funny because what is happening to this garage door is not making sense to what is showing up on the screen every time I look at now if I figure out what is going wrong with this wall switch controller and I can get it working properly again I might find this humors in some sick way

But if you have followed the issues that I have had with this particular garage door opener I would have gone with a different brand but this is not your normal garage door opener because this metal garage has very high ceiling and there is no easy way to put a normal garage door opener

[CapLeaker]

But if you have followed the issues that I have had with this particular garage door opener I would have gone with a different brand but this is not your normal garage door opener because this metal garage has very high ceiling and there is no easy way to put a normal garage door opener

My attached garage has a high ceiling. So my door goes up that high that I can drive a full size tractor with a cab in and out without thinking on hitting anything. My openers are made by Linear. While both doors lift the same height, one door lifts double width no problem.

[redwire]

Bueno, sam_sam_sam, no proporcionas el número de modelo. Me pregunto qué modelo es. Si tan solo supiéramos el número de modelo.
¿Alguien lo sabe?

I wonder what model it is. If only we knew the model number. Does anyone know? Somewhere can the model number be found? I don't think I know the model number. It must be high up there.
You can reset the wall switch, one was recalled and they were giving out a repair kit. The firmware is shit and the door would close ignoring the obstacle sensors, squish children and babies if you pressed the Enter button more than once.
I forgot what model that is.

[sam_sam_sam]

Update once I replace the wall switch controller it came back to normal life again wow not exactly sure what happened to the original wall switch controller
I had posted earlier in another post about the garage door opener not staying online all the time well this is all gets interesting as well I was told by tech support to get a gateway switch for my garage door opener and this should resolve the issue well not exactly because I could not get it to work correctly ( this was the first one that I bought ) when I called tech support again about the same issue again I was told that this gateway was issue to someone else and we tried to register it to me but it refused to reset wow really so this tech support person ordered me new one and I was not charged for this so the second one showed up and I tried to get this one to connect same exact thing happened again would not connect to my garage door opener again so I called tech support again and this time there telling me that they see the gateway controller but still refusing to connect wow really

I had a brain storming idea what would happen if I unplug the garage door opener for 30 seconds ( this has a battery backup system in the opener ) and tried to connect to the garage door opener this way and follow the installation process this way no where dose say to unplug the opener to setup the gateway controller but guess what this is exactly what needed to happen for it to connect to the door opener wow really are you kidding me I am not impressed with the way this controller is setup so far it has not gone off line

[sam_sam_sam]

It has been online since Sunday afternoon and has not gone off even with the 30 minutes that the power was off this morning at 2:30 and came back on at around 3:00 am this morning so as far as I am concerned this issue has been resolved so far

[CapLeaker]

That’s good. What a weird garage door opener… I guess I have to keep my old ones running, lol

[redwire]

It's too bad we don't know the model number.
A problem is the firmware cannot be updated so bugs exist and also between the opener and wall switch comms. They are complicated now, for something with a few digital outputs and inputs, very little I/O.
As I mentioned, some bugs are serious and they have to do a recall so it doesn't squish children. They quietly will do a board swap to get the updated F/W to customers if it's a buggy thing. The F/W is supposed to be high quality because of the safety aspect but Chamberlain/Liftmaster group is more about profit and keeping it cheap construction.

[sam_sam_sam]

The tech support solution has worked well without an issue so using there recommended gateway so I can not really complain about that but the installation instructions are not correct and they should change them so other customers do not have issues getting it connected

[redwire]

We don't know the model number to check the instructions, I can see a need to cold reboot the whole thing. Again, some units had a recall over safety with their bad firmware.