Linear Garage Door Opener Control Board Repair weak capacitors

[sam_sam_sam]

I was having issues with the controller not always responding to remote control signal having to hold button until garage door started to move

Now after replacing the two capacitors on the two 5 volt power supply rails

One is used for the up/down limit up/down force circuits

Second one is used for the radio receiver circuit

The main filtering capacitor ESR value was a little higher than a new one

https://www.northshorecommercialdoor...yABEgLxlvD_BwE

https://sep.yimg.com/ay/yhst-1641663...l-board-45.gif

I also have issue with the down force limit circuit is weak but it is very hard to follow on this circuit board right now I have it closing again but the door is much lower than it was I barely go under the door with out hitting my head I going to try to adjust it back up a little higher and see if it starts tripping again

If it does I will buy another controller board from this company and try to repair the one I have

[redwire]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

... Now after replacing the two capacitors on the two 5 volt power supply rails

What happened after you replaced the two? I would replace the main filter capacitor I think it's 470uF but some boards upsized it to 1,000uF.

The limit trimpots might be dirty or got bumped when you took out the board. I find these door openers need lube as well.
But in this hot weather my opener (not Linear) is also needing many button presses to open/close sometimes and I haven't tried retuning the remote to see if that fixes it. New batteries did not make a difference.

[sam_sam_sam]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

I sent the place that is offering this board an email about this issue and I going to see what there response is to this issue

After I replace all three capacitors the the garage door controller responds a lot better to the remotes

I had turned the pot control back and forth several times and when it kept tripping the over current limit I turned the pot back and forth again several times which did not make a difference until I change the setting for how high the door opens then it stopped tripping the down force limit

The up force limit has so far has not been an issue it has always been the down force has been the issue

I do not have a 1000uf at 35 volts that the diameter is going to be to big but I had considered this at first if fact the 470uf@ 35 that I have just barely fit in the space that is available for this capacitor

I can easily open and close the door by hand so I know that it is not the issue

One note this issue with the down force was doing this way before I took it apart
I took apart to try to figure out why the down force was giving so much trouble

I had another Linear Garage door opener that got struck by lightning on the door sensors i had to replace that controller board twice for the same exact issue until it happened the third time and had fried the motor then I had a new garage door opener which is the one I have now which is over 5 years old now

[sam_sam_sam]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

But in this hot weather my opener (not Linear) is also needing many button presses to open/close sometimes and I haven't tried retuning the remote to see if that fixes it. New batteries did not make a difference.

I would look at the controller board and see if it has two 5 volt rails where one is for the radio and one for the up / down force and the up / down limit because this how this one is setup

And of course I would charge all of the capacitors on the controller board just for good measure

[sam_sam_sam]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

The garage door opener took a complete shit I will have to replace it again the up force went haywire again and the up limit was not limiting the door so the chain broke and I had to manually close and lock the door

[redwire]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

That sounds terrible, I hate drama with garage door openers.
But the new ones are super junky - wimpy brushed DC motor, thin plastic gears, thin rails and frame, slow as molasses and cloud-based app using WiFi to the Borg hive. So I'll repair the old one as much as I can.

Most garage door openers, including yours use a tachometer slotted-optical encoder to monitor speed and trip if motor speed drops. This is how the jam detection is done. They just assume the motor slows down. The encoders are sensitive to dirt/dust and the LED's do fade out with age. It could be dirty phototransistors or failing LEDs, and a new board would not fix that. Blow some compressed air at them, and the encoder wheel. Check you get near 5V (blocked) and 0V especially (unblocked) output, at their connector.

Check your motor start capacitor, that would also cause false trips of the jam detect if the motor is running slow due to that cap being low value.

A few manufacturers added two MOV's (kit) on the incoming mains to stop them from blowing boards due to lightning and power surges.

For my control board, I am ordering all new caps and motor relays and will make a thread about it. Right now it's just unreliable, taking many presses of the remote to do anything, and at close range, despite new batteries.

[sam_sam_sam]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

I am not going to throw out the old one but I need a reliable garage door opener which right now this same exact model is still being made so when they come I going to request that I get the same exact model again

[keeney123]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

I am not going to throw out the old one but I need a reliable garage door opener which right now this same exact model is still being made so when they come I going to request that I get the same exact model again

These things could be made so simple as far as the motor running forward and reverse to lift the door up and down. I worked on one made in 1977 and it was very simple. The problem comes with safety issues as when those units fail, they can crush a child.
I actual look into designing a unit for this 1977 unit. Before I could get down to the unit with my design the person through the whole unit out. It had 2 sets of Limit switches for travel were used in these units. This could be increase to 4 to make that part failsafe. The unit had one solenoid that directed the motor to switch between up or down. I would have scrapped the solenoid and put in two relays. One for up, one for down for the speed and two separate switches one for up, one for down. The motor had a thermal sensor for overload I would have left this alone. The radio control circuit was connected to where the manual switches connected. It worked just as a switch; they just monetarily closed the circuit to activate the motor. The safety issue on this unit was lacking as it said it was a prototype model. I had intended to use 3 lasers lights at the door opening. These would always be active and without the connection the motor would not turn on. That is one light traveling across the lower opening of the door to a receiver, times that by three at different levels so as to make sure nothing is blocking the light. The circuit could either be made to back up or just stop the motor a pond blockage. There were no electrolytic caps in the whole circuit. Why I tell you this is you might want to consider taking the old unit and design a system for yourself and perhaps my experience with this old garage door opener would give you some ideas to consider in your design.

[sam_sam_sam]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

I might just do this but right now I need to have a working one but I have given this some thought

[keeney123]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

I might just do this but right now I need to have a working one but I have given this some thought

I am sure you will find a good working one. You have a good mind so just trust it.

[sam_sam_sam]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

Well I finally figured out what happened to this garage door opener it turns out that the receiver module for the door safety sensors was acting up randomly sometimes it would work correctly and sometimes it would not I replace it with the new one that came in the box and so far it has work flawlessly sense then

I have never seen a door safety sensor failure like this one they either work or they do not work
But this would sometimes work and sometimes not work I check the two capacitors on the little board and they are in specifications so it might be the optic sensor failure of some type

I will now order a new door safety receiver module and a new chain coupling rod to repair the original door opener and keep it for a spare unit

[keeney123]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

Well I finally figured out what happened to this garage door opener it turns out that the receiver module for the door safety sensors was acting up randomly sometimes it would work correctly and sometimes it would not I replace it with the new one that came in the box and so far it has work flawlessly sense then

I have never seen a door safety sensor failure like this one they either work or they do not work
But this would sometimes work and sometimes not work I check the two capacitors on the little board and they are in specifications so it might be the optic sensor failure of some type

I will now order a new door safety receiver module and a new chain coupling rod to repair the original door opener and keep it for a spare unit

We are always learning in life. I try and always allow for anything to happen. I usually go by probability. However, I keep possibility in the back of my mind. With possibility I use Quantum Physics as a guide meaning most anything can happen.

Good for you for finding the failure.

[sam_sam_sam]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

Good for you for finding the failure.

When I can not answer a question about what failed on something I keep trying to figure out what has happened to it but sometimes it is a while before I figure what has happened to it sometimes when working on something else that when I find the answers to this question on the first device and sometimes it helps fix the second device and sometimes it what I have read on the BadCap forum that helps me understand something I was not sure of exactly how something works

( yes you could call an obsession sometimes to just about to the point of udder madness that when I have to drop trying to figure it out either because I do have the information that is needed to understand what is the issue with the device or I do not understand the issue I think that I am seeing with the device )

This one thing about this forum I have learned a lot about a lot things that I had no idea how or where to being to fix something this is the reason why you see me post things that I am working on to get ideas and point me in the right direction so thank you for all you for sharing your wisdom

[sam_sam_sam]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

I can definitely tell you that it was the door safety receiver module that was the issue because I have had no issues sense replacing it

[keeney123]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

I can definitely tell you that it was the door safety receiver module that was the issue because I have had no issues sense replacing it

There you go.
Can the module be taken apart to find the component problem?

[sam_sam_sam]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

Yes but I have to research the numbers on the optic sensor and see if I can find a replacement or just buy another service kit for the garage door opener and be done with it I have not had time to deal with problem yet

[keeney123]

Re: Linear Garage Door Opener Control Board Repair weak capacitors

Yes but I have to research the numbers on the optic sensor and see if I can find a replacement or just buy another service kit for the garage door opener and be done with it I have not had time to deal with problem yet

Most likely your kit is going to be the cheapest and quickest way to solve the problem.

Still, it is good to know what exactly failed. To determine if the design is bad or you just had a failure.

Also, if you design your own circuit, you then learn what the challenges are to design the circuit. It will create another type of awareness for your that just replacing boards will not do so that when you go to buy something your more aware of what is a good buy.