Diagnosing garage door sensor problem from technical viewpoint.

[@arniecummings983]

Your simple wiring diagram was the key to enabling me to understand, diagnose, and repair a wiring problem, which was essentially disconnected sensor wires in a jumble. That diagram was flashed quickly at the beginning of the video, so I had to take a screenshot to have time to adequately digest it. Your simple diagram was far better than more complicated ones in other installation and troubleshooting instructions. As complicated as it needs to be, but as simple as it can be. Well done!

[@magicarpetmoto]

I second this

[@thepar7575]

One of the best summaries on diagnosing the sensors. Simple and understanding.

[@ericharnish4792]

Thanks for posting! This is the video that helped me diagnose the issue: Bad sensor. Popped in a new set and we're up and running! The wiring diagram was clutch. Much appreciated!

[@BetaBuxDelux]

Awesome work - my sensor is bad - your video helped me out! Thank goodness there are videos like this for those of us without dads to explain this stuff.

[@vinceteti1216]

Awesome explanation, I had no light on either sensor. I thought the sensors were bad. After doing the test you suggested I was able to diagnose the wiring was bad. Thank you.

[@dancindavey1515]

Great explanation and simple diagram. Think you solved my dilemma. Thanks! This is how how- to videos should be done for novices. And thanks for answering all the questions. One of them kept me from making a mistake of using ac instead of dc.

[@TheSupertramp11]

Very good video explaining the possible low voltage issues one may have with garage door sensors. Thanks!

[@SuperManny1952]

Very concise and to the point explanation with diagram😊😊

[@moi28642864]

Thank you so much for the video my sensor harness turn out to be 2.7 volts but the red one did not light up so I went to lowes bought new ones and now we’re back on business Genie sensors

[@ccbest21]

Just watched this and it was very helpful in diagnosing the problem. So I traced the wire to the pinched section and cut it there. It wasn’t too far from the end thank goodness and re-spliced the wires and now it’s working thank you

[@eddiec3961]

Thank you for posting.. what if both sensor lights are off?

[@MethodOverRide]

Exactly what I was looking for, thank you.

[@osvaldoorellana1584]

Thank you so much you saved me hundred of dollars in repair!

[@markchidichimo7761]

Thanks for taking the time to make this.

[@JosueDQ77]

Thank you for this video. I can diagnose that my sensor is bad since the voltage is present.

[@yj4rocks]

Did you check the voltage across the green sensor when running the garage door up? My voltage drops down to 7V and the green light flickers and sometimes will stop the door.

[@bleung2]

I had find out the both green and orange sensor have no light but if i took green sensor wire out from the power supply in garage opener then other orange light sensor is on. Im really confusing why it doesnt work. Can you please advise ?

[@IMZReady4Anything]

Can you put a jumper wire some where and eliminate the sensors?

[@mrtodd3620]

You could connect black to white I suppose, and just rely on the wall switch. Why don't you try it and report back and let us know if the operator is still working. I have never tried it and don't know if anything would break in the operator by doing so.

[@TonyBombardo]

My issue is that both sensors are lit up and one light will turn off if my hand is in front of it, but the door just acts as though its being blocked and auto-reverses no matter what I try .

[@andredsouza2320]

thank you for the explaination. I have a genie powermax 1500 and the sensors are pointed appropriately, and lights on both units are on, indicating that the sensors are aligned, but the door is stuck open and will not close. ANy ideas here?

[@doctor_risk]

Getting 10 bulb flashes on Sears Craftsman indicating that it's a sensor problem. Garage door doesn't close unless button is held on wall unit. Both sensors show a green solid light and appears to be clean and pointing towards each other with no obstructions. What could be wrong?

[@damonmcelvain4941]

Everyone else deals with blinking. Thanks for video on no light.

[@HollywoodMGB3]

If you are getting less then 11 V at the unit, is the unit bad?

[@etot6064]

Will the door refuse to open if there IS a connection across the 2 pins or if there ISN’T a connection?

[@doloresgill6366]

I have a Lunear garage door opener. One has a green and red light the other just a green. It will not close with controls but will with the big one on garage wall. What to do?

[@schenkkohain]

What gauge wire did you buy? Thanks! Same issues. My dad insisted I use a stapler to do it. It worked fine, but then it didn’t in a few hours.

[@pennysmith2893]

One sensor on Overhead Door make is not working. I cut the wires to it and tested the wires coming from the wall and got a negative reading using dc on multimeter. Switched the testing tips and its still reading negative. Is that normal? I’m thinking I need to replace ONE of the sensors. Thank you.

[@mrtodd3620]

The sensors come as a pair. You can get them at Home Depot. May even come with wiring. If you get around 11 v dc between contacts at controller, and not across the sensor, then change the wiring. In your case, I would just change wires and sensors and call it good.

[@quaisoncrosby-4p1sab36]

This was extremely helpul!!

[@anciagabe7804]

I have a Chamberlain and the voltage for the door sensors are 6V DC "The output voltage for the door sensors should be between 5-6 volts DC "

[@zuluhours]

Great explanation. Nice & simple 👌

[@knafis]

In my case on the unit i got 6.95 On the sensors both got 6.95 And both sensors led is off I m suspecting sensor but not sure any opinion

[@pecosR0B]

so do I just use my multimeter (total noob with multimeters, bought one today) and place a black and red lead on the two screws of the back of a sensor to see if it reads 11 (or similar voltage) while in the DC mode? I suspect my logic board is out since I installed new sensors and no lights are on either side - I don't think my wires are damaged since they are in the ceiling and walls but you never know. If this is a logic board issue I'm going to just buy a new unit since it's half the cost of a new unit

[@mrtodd3620]

As I show in the video, check for voltage between the two screws on the operator, and then same for each sensor. All three points should have the same voltage. If incorrect voltage at the operator, change the operator. If incorrect voltage at the sensors, change the wiring. If correct votage at the the sensors, change the sensors.

[@fdhall]

My green side is getting like half the voltage when I connect the wires. My voltage is reads ~12v at the wires themselves then like ~6v when I connect and measure at the prongs. I've already replaced both sensors with new. Thoughts?

[@fdhall]

Looks like there's a bad wire. After watching your video I didn't realize those sensors share the same wiring pretty much. To test, I just ran a wire from red side to the green side and voila... bob's your uncle😂 Thanks buddy...this video got the juices flowing for a really easy fix👍🏾

[@avtarbhogal7024]

Thank you for the great tips I have no lights on the both sensors. Do I need to buy new sensors? Thanks in advance I have genie h400a

[@mrtodd3620]

I am going to give you a flow chart as if you are working on the machine in my video: Check for 11vdc between the contacts on the controller. If you get 11vdc, then check for voltage between the contacts of each of the sensors. If the voltage is 11vdc at the sensors and you don't have any lights on the sensors, then replace the sensors. If the voltage is correct at the controller but not at the sensors, then replace the wiring 1st.

[@avtarbhogal7024]

@@mrtodd3620 thanks for replying I dont have any tester but I did buy new sensors tried connecting directly to the unit no power.

[@mrtodd3620]

@@avtarbhogal7024 I would imagine then that you have a problem with the control unit but you really need to buy yourself a multi meter. You can get a fairly decent one at home depot for around $30. Only with a multi meter can you really test what is going on.

[@ricearoniification]

What if neither the red light nor the green lights are on but I have power to the opener head?

[@Ricksp65]

Just was working on mine thought I had an issue The sensors lights on either tried replacing the wiring but I’m only getting 6.3 V out of the terminals in the back of the opener my guesses the board is probably shot what do you think.

[@rodneykahn6927]

my sensors light up and appear to work properly, but the door wont go down, and unit flashes 10 times. Chamberlain tech support said could still be a wiring problem, not bad sensors. The sensors could be getting power enough to light the leds, but a bad wire connection can screw things up. The way to check bad wiring is called the short wire sensor test.

[@ebellyfish4256]

Silly question, but isn’t the unit plugged into an outlet, so shouldn’t the voltage be in AC? Or is the unit converting the incoming AC voltage to DC voltage for the output to the sensors?

[@joshhykes8822]

Yes, the unit is converting the incoming AC to DC. Almost all electronics/anything with a circuit board will first convert the AC to DC using a device called a rectifier.

[@nancycrisman7496]

Hi Todd, my brothers garage door has problems. The green light was not lit. I moved sensor. Both are lit with solid color now, but garage will not close. Goes half way down and opens back up. If I hold down the inside garage remote, it will close. Can you help me.

[@galvinmitchell4999]

What bout both sensors not lighting

[@isabel99455]

Im having a problem with the sensors i got a new garage door opener and sensors 3 years ago and last week the sensors keep turning off, i unplug the garage door motor and plug it back and the sensors stay on for 1hour and die, what can this problem be? Thanks for your helpfull video

[@chriram25]

My green sensor comes on intermittently. Power is fine, alignment is fine. Door works fine if green light is on. However, the green light randomly goes out and door wont close. Any ideas?

[@mrtaktiks]

Hi, new Genie has 13 volts at motor but zero at sensors and wired wall switch. Door does operate up an down with limit switches. Motor clicks when remote is pressed but nothing happens. Retraced wires 10x's and do not see any irregularity. Sensor swich connectors shox audible meter continuity. Sounds like a bad wire? BTW the Genie door is of very poor quality. Would never buy again. Threw away box so probably can't return. Call Genie and a lady with an algorithm chart reads it off. What would you do?

[@shaunnavarra3395]

What could the problem be when one of the sensors has a loud buzzing sound that stops when I block the beam? I even replaced both sensors and still a problem. New motor unit too.

[@mrtodd3620]

Seems like you have replaced everything there is to replace, except the wiring. Could there interference from an outside source? Maybe others can add something to your problem.

[@pinoyautomotogpsmaster220]

WONDERFUL VIDEO PRESENTATION

[@SonnyJ3t]

What if both lights are green, however, the garage door does NOT stop when tripped? Does that mean the power wiring is correct, but the "trigger" wiring is incorrect?

[@geniusbboy]

thanks, but if both led working ,is it possible that the sensor is bad,?

[@mrtodd3620]

I don't understand your question.

[@hhvphomemovies2004]

Can you install more than one sensor pair, say one pair at 6" from the floor and another pair at 36" from the floor?

[@mrtodd3620]

I don't think you can very easily. I think that while one set of sensors would have a broken beam the other set could have a closed beam and door would still come down. I wonder if there is a product out there that meets your need, why don't you surf around and post it if you find one.

[@Jpeezy65]

thanks man, you saved me a bunch of time

[@dancindavey1515]

Jpeezy Patterson As well as money.

[@OneManParade]

Why did you test in DC voltage? Isn't a garage door opener AC? Just asking.

[@mrtodd3620]

The sensor circuit is dc, but the door opener motor is ac. It is not uncommon to have two types of power in one appliance.

[@XiangshiYin]

Thanks for posting the video, it helps a lot! I have a similar problem where one of the sensor doesn't have any power input (zero volt on the sensor's screw nuts) and the other sensor has power. However, all the wires goes inside the wall. What could be the best way to replace the wiring in this case? Thanks!

[@mrtodd3620]

If you have power at the main unit, but not at one of the sensors, then run a new wire set to the sensor in the best way you can. Run it along the ceiling or wall. It really doesn't have to be pretty.

[@XiangshiYin]

Good point, I was thinking of the same way. Running a wire through the wall isn't easy.

[@Rj-gr7is]

Neither garage door sensor lights up, bought a new control board installed it same problem. So I did a sensor bypass with 1 ft of wire and it worked, so then I replaced both wires and am having the same issue please help

[@xminiman10x]

Im having the same issue. I replaced with two sequencer boards and neither of them fixed my low voltage on terminal screws 3 & 4.

[@Rich-it1mc]

Thank You !!!

[@adamandrew1614]

My question is: My sensor was blinking and is now off. I am getting a reading of a very low voltage (don't have a device that measures it actually, just have one that beeps), but it barely beeps, when I have tested the wire lines. I have a black, green, red, and yellow...coming out of the wall and my sensor has a white/black and white connection. I can't figure out if I am wiring my sensor correctly to which wire type (I've watched you tube videos to no avail). The light won't come on and I've tired many different combinations. Any suggestions?

[@mrtodd3620]

You can't do this repair procedure without a multi meter. Any other tester besides a multi meter will not work for this repair procedure. You can get a decent one at a fair price at home depot. If you decline to get a multi meter, I would replace all the wires and both sensors according to the wiring diagram in the video.

[@pwgeeg845]

what if both lights are lit properly but the door still will not close. The troubleshooter info suggests that for three blinks, you have a sensor problem. What sensor issue could exist if both are lit properly?

[@mrtodd3620]

Check to make sure that you get the right voltage drop across each sensor. If you do, then replace the sensors and see if that fixes your problem. Every machine is unique, I don't know how they all work so my video was just general information.

[@robertpendergraft4459]

Why did you use DC instead of AC?

[@mrtodd3620]

The sensors are dc, not ac.

[@dancindavey1515]

todd No wonder I couldn’t get a reading. Didn’t notice till I read this reply. Thanks also to Robert.

[@TheWilliedoyle]

good lesson

[@daviddunning4518]

Thank you Todd

[@avtarbhogal7024]

I find out the circuit board is bad I found some burn Mark's one side 46.00 on ebay and 73 from genie I got the o g part thanks

[@mrtodd3620]

That makes sense, if you are not getting dc voltage between the two contacts.

[@Johnny53kgb-nsa]

One of my sensors has a yellow, or amber, light and the other a green light. It's a Chamberlain Liftmaster unit.

[@mrtodd3620]

I don't think that light colors really matter, they all work the same imho.

[@oldarkie3880]

The yellow is a sender and the green is a recover.

[@theinfinityshield]

Upgrade your sensors to Infinity Shield sensor. Those photo eye have so many issues!

[@daviddunning4518]

What if neither lights are lit?

[@mrtodd3620]

All the wires go back to those two connection points on the motor unit. Set your meter to volts dc and put a lead on each contact and you should get around 11 volts dc between them. If you do, then your lack of lights on both sensors is probably due to a broken wire. If you don't get the expected voltage reading, then you probably have an issue with the motor unit. Of course, you should make sure that your motor unit is getting 120v at the outlet it is plugged into.

[@avtarbhogal7024]

David did you get your sensors lights going? I have the same issues my circuit board have burn Mark's so I am getting new one that should solve my problem

[@bwagenberg]

You mean the green (receiver) is flashing. How do they transmit the "connected" signal through the power pair. Please redo this video with a thorough explanation.

[@mrtodd3620]

I wish I could. All I know is that one side sends a signal to the other, and if the beam is unbroken, the receiver lets through a voltage level to let the head unit know it is okay to operate. I would guess that the 11 volts dc is what is needed to operate, and if the beam is broken or the sensor system is broken, that 11 volts will drop to zero, but I haven't tested it that way. Why don't you break the beam and report back?

[@daviddunning4518]

I notice when moving the sensor wires coming out of the unit, the amber light above the learn button goes on and off, it then stays off when I stop moving the wires Does this mean anything?

[@mrtodd3620]

I don't know the fine points of how each product works, and I am actually just a dyi-er when it comes to garage door openers, but I think some units have a learn function where you pair your peripherals to the head. But back to your op, did you get approx. 11 volts dc between the two contacts on the head? If you have to wiggle a wire to get that voltage, then maybe there is bad connection somewhere. If you don't want to open up the unit to see what is going on, then I suspect just replacing the whole thing will be a quicker fix.

[@networth8754]

How frequently is it a bad sensor vs. the wiring? My sensors are 20 years old.