Garage Door Won't Go Down

[Gebo]

That transformer is fried, it happens and it will cause logic board issues. Check the input and output to the spec on the label. Another reason for erratic operation is week door springs causing changing loads on the lift mechanism.

Springs replaced in 2018. And that was a scary deal.

 

[hrv]

This is probably not going to help but I had an intermittent problem with my door not going down but only in the afternoon. I went through many of the same troubleshooting procedures you have without any luck. Just by chance I happened to notice that the afternoon sun was shining directly into to sensor. If I shaded that sensor the door worked. I ended up clipping a piece of cardboard on top of the sensor that extended out about 3 inches and shaded the sensor without getting in the way of the beam. I have not had the problem since.

Had the same issues years ago and I got a new logic board and the problem was solved... It is a easy do it yourself job...While you are in there look at the capacitor too and lube the gears...By the way I have a Chamerlian too 1/2 HP and it was installed in 1998...Still works great..I lube the unit and the door once a year....

 

[Donald]

I like the newer openers that are mounted next to the garage door and roll it up or down from there. As opposed to hanging from the ceiling.

 

[Warstud]

If you have to hold down the button....... then maybe you need a new button .

 

[Gebo]

If you have to hold down the button....... then maybe you need a new button .

I tried a new button. It’s not the button.

 

[Nukeman7]

I have a Chamberlain 1/2 hp garage door opener. I have an intermittent problem in that it won't go down about 75% of the time. Now if I hold the button on the wall switch I can force it to go down. When it doesn't go down, it will do down about 1 to 3 feet and then stop and reverse. The warning light flashes. It acts like something has blocked the eye sensors but nothing is in the way. I tested the sensors and they are both on and
when I stick my hand between them the lights go out so I know they are working properly. Me being the OCD guy I am, I had another sensor and another wall unit. Replaced them just for kicks and it didn't help. I took off the actual panel box surrounding the limit switches to see if they were
working properly. When the door shuts and opens normally the limit switches open and shut like they should.

When it starts to go down 1 to 3 feet and reverses, how many times will the warning lights flash? Is it 10 flashes or only 2 flashes?

Also, can you post a photo of the type of control panel or switch button that you have mounted on the wall?

 

[Torrid]

Have you tried resetting the limits on the garage door? I've had it forget it's programming if the power goes out for an extended period of time. I'd look up the process for your unit and give that a try if you don't have any sensor alignment issues.

 

[Gebo]

When it starts to go down 1 to 3 feet and reverses, how many times will the warning lights flash? Is it 10 flashes or only 2 flashes?

Also, can you post a photo of the type of control panel or switch button that you have mounted on the wall?

I have it disassembled now. It flashed more than 2.

 

[Gebo]

Better focus.

 

[Nukeman7]

Thanks, Gebo. I was curious because the Chamberlain troubleshooting guide says it will only flash twice if the "Lock" mode has been activated, but 10 times if it is a safety light/sensor misalignment issue. If it flashes 5 times, that indicates an obstructed travel path or too much resistance from the door track/rollers/springs, thereby requiring downforce and/or travel stop readjustments per the instruction manual.

When my safety light/sensors went bad about 5 years ago, I had a spare set and just disconnected the old sensor wires from the GDO unit and inserted the wires of the new sensors in their place. Then I held the sensors 2 inches apart and had my wife press the wall switch to verify the new sensors would fix the problem before going to the trouble of installing them. I also discovered that the new style safety sensors (with Green and Yellow lights) sold by Chamberlain today wire up differently than the original style.

Here is a link to Chamberlain's Troubleshooting site:

Chamberlain Liftmaster Troubleshooting

 

[WylieCoyote]

Whenever I've had a door suddenly start doing this, I would just decrease the reverse sensitivity a little bit. Usually fixed the issue.

 

[Gebo]

Thanks, Gebo. I was curious because the Chamberlain troubleshooting guide says it will only flash twice if the "Lock" mode has been activated, but 10 times if it is a safety light/sensor misalignment issue. If it flashes 5 times, that indicates an obstructed travel path or too much resistance from the door track/rollers/springs, thereby requiring downforce and/or travel stop readjustments per the instruction manual.

When my safety light/sensors went bad about 5 years ago, I had a spare set and just disconnected the old sensor wires from the GDO unit and inserted the wires of the new sensors in their place. Then I held the sensors 2 inches apart and had my wife press the wall switch to verify the new sensors would fix the problem before going to the trouble of installing them. I also discovered that the new style safety sensors (with Green and Yellow lights) sold by Chamberlain today wire up differently than the original style.

Here is a link to Chamberlain's Troubleshooting site:

Chamberlain Liftmaster Troubleshooting

Me being OCD, I have both new sensors and a new limit switch and new wall switch. I swapped out the sensors and the wall switch and same problem.

 

[Gebo]

Whenever I've had a door suddenly start doing this, I would just decrease the reverse sensitivity a little bit. Usually fixed the issue.

After disassembly, the limit switch is working properly. I watched it functioning as I raised and lowered the door.

My problem “has” to be the logic board and apparently the overheated transformer.

 

[hrv]

Better focus.

This is the exact one I have... Installed in 1998 and still running. I did replace the logic board for a issue like you are having...Fixed the problem.. I replaced the capacitor once.. Lubed the gears inside while I had the logic board out. I also lube the entire door and chain once every year...I had the springs replaced once over the years. I mist the springs with wd40 once a year also....

 

[Rogueman2016s]

I have a Chamberlain 1/2 hp garage door opener. I have an intermittent problem in that it won't go down about 75% of the time. Now if I hold the button on the wall switch I can force it to go down. When it doesn't go down, it will do down about 1 to 3 feet and then stop and reverse. The warning light flashes. It acts like something has blocked the eye sensors but nothing is in the way. I tested the sensors and they are both on and
when I stick my hand between them the lights go out so I know they are working properly. Me being the OCD guy I am, I had another sensor and another wall unit. Replaced them just for kicks and it didn't help. I took off the actual panel box surrounding the limit switches to see if they were
working properly. When the door shuts and opens normally the limit switches open and shut like they should.

I took off this piece here looking for broken solder joints but couldn't find any. The one thing I did discover is the black 204C0137 box is hot as fire.
It will burn my fingers. It was completely rebuilt in 2018.

Any direction? Suggestions?View attachment 194551View attachment 194552

Replace the board

 

[Gebo]

This is the exact one I have... Installed in 1998 and still running. I did replace the logic board for a issue like you are having...Fixed the problem.. I replaced the capacitor once.. Lubed the gears inside while I had the logic board out. I also lube the entire door and chain once every year...I had the springs replaced once over the years. I mist the springs with wd40 once a year also....

Do you remember where you got the replacement logic board? eBay?

 

[hrv]

Do you remember where you got the replacement logic board? eBay?

It was a few years ago and I do remember I ordered it online but dont remember the site...

 

[Gebo]

I’m gonna call liftmaster tomorrow and see what’s available for a direct replacement bolt on head unit and then ask them about the purchase of a logic board. When I rebuilt both units in 2018, they were extremely helpful.

 

[vwmaniaman]

I would suspect the Regulator that looks like a transistor next to the transformer and the blue capacitor beside the transformer. Regulators bring the voltage of the DC down to lower voltages for use by the 5Volt circuits. That Blue capacitor would be the first thing I suspect. In all my years of electronics repair, it is usually a bad capacitor that causes circuits to fail.

 

[Rogueman2016s]

I would suspect the Regulator that looks like a transistor next to the transformer and the blue capacitor beside the transformer. Regulators bring the voltage of the DC down to lower voltages for use by the 5Volt circuits. That Blue capacitor would be the first thing I suspect. In all my years of electronics repair, it is usually a bad capacitor that causes circuits to fail.

Or a resistor. Causing another component to get more power then it should.