Chamberlain Model # 139.53664SRT 14LG0607B 14PC4 logic board Schematic

[strobes]

Well some one asked me to look in to this board. All works but remote, I suspect a defective component, most likely a cap.
Bad part I don't have a liftmaster garage opener to power on the board. And need schematics to connect power, etc.
Unfortunately google did not help or I missed it. Any ideas where to find wiring diagrams at minimum?

 

[BillK]

Have you reached out to Chamberlain ? I am sure they will have at least wiring diagrams probably on their website. Do you have a way to check the remote itself to make sure it is working ?

 

[BurtEggley]

my unit requires programming the remote to the opener. Did by chance the owner try to reconfigure it after a battery change etc., and mess up the programming? The procedure should be in their manual.

The other issue I ran into is that if it is an older unit - 6 to 7 years old, security cameras may interfere with the remote. An ex-neighbor added a security camera on their garage that is about 30' from my opener. It hosed my opener's remote strength by overwhelming the receiver. We had to use the remote right up against the garage door to be close enough that it would work. We extended the antenna to the header above the door and that allowed it to work from a reasonable distance, but no where near where it was before their camera. Every time someone added a camera nearby the distance got shorter. Finally I just replaced the opener because the newest ones use I think three frequencies at the same time to overcome things like this. The opener prior to that one would do the same thing when one particular leaf blower was running. The electronic emissions from one neighbor when he was blowing leaves would overwhelm the opener.

The point being that there may be nothing wrong with the board.

 

[djbmw]

Well some one asked me to look in to this board. All works but remote, I suspect a defective component, most likely a cap.
Bad part I don't have a liftmaster garage opener to power on the board. And need schematics to connect power, etc.
Unfortunately google did not help or I missed it. Any ideas where to find wiring diagrams at minimum?

This guy has a video of him testing one...

Ps... did you inspect the solder joints under magnification? Hairline solder cracks can cause all kinds of chaos

 

[strobes]

I'll check with Chamberlain next year . The owner has two identical garage openers. And swapped board between two. So the problem followed the board. Attempts were made to reprogram too. Thanks for the video. Yes checked solder joins, dont see problems but plan to re-flow them anyway....I was hoping for schematics to check some points with a scope.
Happy New Year!

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[djbmw]

I'll check with Chamberlain next year . The owner has two identical garage openers. And swapped board between two. So the problem followed the board. Attempts were made to reprogram too. Thanks for the video. Yes checked solder joins, dont see problems but plan to re-flow them anyway....I was hoping for schematics to check some points with a scope.
Happy New Year!

​

Sounds good. Apparently, based on a few reddit posts, the 5V 3-terminal linear regulator, L7805CV, seems to fail (Red arrow pointing at it below). The cap and resister that I've also circled should be tested as well, while you're at it - ideally out of circuit.

 

[strobes]

Sounds good. Apparently, based on a few reddit posts, the 5V 3-terminal linear regulator, L7805CV, seems to fail (Red arrow pointing at it below). The cap and resister that I've also circled should be tested as well, while you're at it - ideally out of circuit.

Thank You! I'll check and report back.

 

[strobes]

Thank You! I'll check and report back.

Looks like this part is OK. I connected 110v to the board. Clean 5v from the L7805CV. The diag LED flashing ones indicating missing safety sensors. So need to figure out how to bypass this condition. ( dont even know to which terminal these sensors should be connected to. so more googling and youtube..)

 

[BurtEggley]

$54 for an exchange board from a guy on ebay who fixes them. What is your time worth?

goes by "LiftMaster, Chamberlain, Craftsman 14LG0607B Logic Board Mail In Repair Service"

 

[strobes]

yes, but an opportunity to learn and

 

[BurtEggley]

Ok, I'll buy that. Ask the guy will sell you a kit of the most common failure parts and a schematic of the board to fix your own.

 

[walta]

Looks like this part is OK. I connected 110v to the board. Clean 5v from the L7805CV. The diag LED flashing ones indicating missing safety sensors. So need to figure out how to bypass this condition. ( dont even know to which terminal these sensors should be connected to. so more googling and youtube..)

It is pretty much impossible to “bypass” the sensors. The sensors report to the board their status with serial data. Without the correct set of pulses, you are stuck with that error. I think the after-market sensors sell for $20 or so.

Walta