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Discussion Forum

GDO Questions + Problems

BossHog | Posted in General Discussion on February 4, 2008 04:57am

Over the weekend I took a look at a garage door opener for an elderly friend. And I’m not sure what the deal is.

Oddly enough – When I found BT many years ago, the first question I asked was about a garage door. I got so many helpful replies that I stuck around.

The opener is a Chamberlain brand, apparently made by “Lift Master”.

The basic problem is that when you hit the button it won’t go down. the doors starts to move, then reverses. and the lights on the opener flash several times, I assume to indicate that the electric eye thingies are showing some sort of blockage.

The first thing I did was check the electric eye thingies. I cleaned the lenses and made sure they were pointed towards each other.

The sending unit on the left shows a steady green light, but the one on the right blinks constantly.

I took some pictures of the back of the unit, and they’re attached. One picture shows how the wires are hooked up, and the other one shows the model number.

The part number is 41A4252-7C I did a google search, and came up with this link:

http://www.superiordoorparts.com/c-50-Liftmaster,Chamberlain,Sears,Craftsman-Circuit-Logic-Boards.aspx

It shows this model number, and that you can buy replacement parts for it.

So I thought I’d go to http://www.liftmaster.com/consumerweb and download a manual to see if it was wired right. But the lift master website says that’s an invalid model number.

So now I don’t know what to do with it. and I’m hoping that you guys will have some suggestions.

COMMAND: A suggestion made to a computer.

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Replies

  1. User avater
    maddog3 | Feb 04, 2008 05:26pm | #1

    I just trudged through the snow just for you and mine are steady green and yellow so try adjusting the blinking one until it stops blinking.. if I pass my hand in front of the green ,it blinks but the yellow one does not change

    .

    .

    .

    , wer ist jetzt der Idiot ?

    1. User avater
      BossHog | Feb 04, 2008 05:31pm | #2

      Thanks fer trudging through the snow for me. Did you have to do it barefooted, and was it uphil both ways ???(-:Passing my hand through where the beam was didn't change either of the lights on this unit.
      Youth would be an ideal state if it came a little later in life.

      1. User avater
        maddog3 | Feb 04, 2008 05:34pm | #4

        I was in my Dr Dentons too !.

        .

        ., wer ist jetzt der Idiot ?

      2. dovetail97128 | Feb 05, 2008 07:14pm | #17

        ""Passing my hand through where the beam was didn't change either of the lights on this unit."" It should. Try adjusting the lights again until both show a steady color. That is the correct indication they are aligned. Also check the connections to the lead wires coming out of the sensor. My installer simply wrapped them together and vibration was making and breaking contact .
        They can't get your Goat if you don't tell them where it is hidden.

        1. User avater
          BossHog | Feb 05, 2008 07:32pm | #19

          " Try adjusting the lights again until both show a steady color."

          I did try adjusting them, but no luck. They appear to be perfectly aligned.

          " Also check the connections to the lead wires coming out of the sensor."

          I checked the wires from the sensors all the way up to the opener. Didn't find any broken wires or loose connections.
          The first job of leadership is obtaining power. The second job is delegating it to subordinates. [JBR Yant]

          1. dovetail97128 | Feb 05, 2008 07:38pm | #20

            Beyond me then. The times I had problems those were the issue. Good luck and let us know what if anything you find out.
            They can't get your Goat if you don't tell them where it is hidden.

          2. LIVEONSAWDUST | Feb 06, 2008 05:33am | #24

            I am no expert, I've had my share of problems getting openers to work properly(thats why I sub out mine now) but i have learned a few things along the way. Usually , if the opener malfunctions followed with the light flashing, it indicates too much resistance to moving the door. First, dissconnect the opener from the door and check to see that the door moves freely without binding. The door should stay at whatever place you stop it without moving. Could be you have a broken spring (even though this happens in the "down" direction, a broken spring will make it "jerk" causing it to sense too much pressure. If the door seems to work O K then adjust the down tension screw to a higher setting  & retry. Hope this helps.

          3. User avater
            BillHartmann | Feb 06, 2008 05:48am | #25

            No On a Sears/Chamberlain/Liftmaster closing overload causes reversal only.It does not cause flashing..
            .
            A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

  2. User avater
    maddog3 | Feb 04, 2008 05:33pm | #3

    also try holding the button down instead of just tapping it, if the door comes down then it is a sensor problem either alignment or a bad part.

    they are sold in pairs for around $30

    I just talked to my guy in town,

    howse that for help .... huh,huh ?

    .

    .

    .

    , wer ist jetzt der Idiot ?

    1. User avater
      BossHog | Feb 04, 2008 05:40pm | #5

      I forgot to mention - Holding the button down DOES make the door go down. I was kinda wondering if the thing was wired wrong. The sensors from both the left and the right are wired to the same terminals on the opener. (White wires in the picture)That doesn't really seem right. But since I couldn't get a manual, I'm kinda in the dark...
      Computers are not intelligent. They only think they are.

      1. User avater
        BillHartmann | Feb 04, 2008 05:42pm | #7

        The wires to connect together, that is the way that is suppose to be.
        .
        .
        A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

  3. User avater
    BillHartmann | Feb 04, 2008 05:40pm | #6

    "The opener is a Chamberlain brand, apparently made by "Lift Master"."

    You have that backwards.

    Chamberlain makes Chamberlain, Sears, and LiftMaster.

    And they are all basically the same.

    The number that you have is not the model number of the opener, but rather one for the controll board.

    Look on the other end of the opener, under the light lense if it has one that end. Some units have labels on each end with only part of the information.

    These units use the same replacement board as the 41A4252-7C.

    4100, 2100, 1100, 710WHC and 711WHC

    You can get manuals here.

    If you don't find the model number, just use one of those above. It will be close enough.

    http://www.chamberlain-diy.com/diy04/instruction_manuals/0,1341,uid-d2hnaWZkY2ZlZg==_164,00.html

    This is an FAQ on the sensors.

    http://www.chamberlain-diy.com/diy04/faq_view/0,1341,uid-d2ZmbmFkZWZiaQ==_1436-id-5,00.html

    This is the replacement sensors that you need if that is the problem.

    http://www.aaaremotes.com/safetysensor.html

    Sears will have them (but with a differen number). Lowes and HD has them, but they might only have them for the newer modeles. many Hardware stores have them.

    These are the ones for the currnet model so that you knwo the difference.

    http://www.aaaremotes.com/lifchamgardo.html

    .
    .
    A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
    1. User avater
      BossHog | Feb 04, 2008 06:05pm | #8

      Sounds like the thing is wired right, so one of the sensors muct be bad. I made a couple of calls, but no one stocks sensors. I'll have to order some for the guy if they'll let me. I really do appreciate the help yet again. Guess you guys are REALLY stuck with me now.(-:
      You're only young once. But you can be immature forever.

      1. DanH | Feb 04, 2008 06:17pm | #9

        One thing to try is to remove one of the sensors and walk it over to the other one. If it's an alighment problem you should be able to get them close enough that that doesn't matter.
        If your view never changes you're following the wrong leader

      2. User avater
        maddog3 | Feb 04, 2008 06:29pm | #10

        try this place, they are Hoosiers so try not to confuse them ....:)
        http://www.aaadooropeners.com/safetysensors.htm
        .

        .

        ., wer ist jetzt der Idiot ?

      3. DougU | Feb 05, 2008 05:00am | #11

        Boss

        On the house we're working on the new garage door did the same as yours, we called the garage door company out and they found a bad connection, I think ground wire? Not real sure.

        Doug

  4. rlrefalo | Feb 05, 2008 04:40pm | #12

    Boss, had the same problem, changed the photo sensors, didn't fix it, had to change the circuit board inside, there was an obvious burn mark on it, parts guy said it was lightning damage.

    1. User avater
      BossHog | Feb 05, 2008 05:01pm | #13

      The danged circuit boards are so expensive, I wonder if it would be better to change the whole opener rather than mess with it.I probably won't be out to look at the thing again until until next weekend.
      As soon as a man climbs up to a high position, he must train his subordinates and trust them. They must relieve him of all small matters. He must be set free to think, to travel, to plan, to see important customers, to make improvements, to do all the big jobs of Leadership. [Herbert N. Casson]

      1. rlrefalo | Feb 05, 2008 05:21pm | #14

        I think it might well be , then you'll have a warranty.

        Rich

      2. gotcha | Feb 05, 2008 06:02pm | #15

        I have the Sears GDO and when that happened to me, I adjusted the up or down sensitivity a tad and it fixed it.
        Owners manual mentioned this may happen.Simple fix if that's the prob.
        Pete

        1. User avater
          BillHartmann | Feb 05, 2008 06:22pm | #16

          "that happened to me,"Did THAT include the light flashing and that you could make it close by continuing to hold down the wall button?.
          .
          A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

          1. DanH | Feb 05, 2008 07:21pm | #18

            It should be noted, though, that both force adjustments were all the way down. Appropriate perhaps for a lightweight tin door, but not much else.
            If your view never changes you're following the wrong leader

          2. User avater
            BillHartmann | Feb 05, 2008 07:57pm | #21

            "It should be noted, though, that both force adjustments were all the way down. Appropriate perhaps for a lightweight tin door, but not much else."So?Reverse on over force on a Sears/Chamberlain/Liftmaster does not cause the light to flash and can't be overriden by holding down the wall button..
            .
            A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

          3. DanH | Feb 05, 2008 10:34pm | #22

            I agree. I was just noting something that was worth observing in the larger context.
            If your view never changes you're following the wrong leader

          4. gotcha | Feb 06, 2008 03:21am | #23

            That I didn't notice. When it gets out of whack on the sensitivity you have to hold the button longer or it goes down about 18" and reverses.I've probably adjusted it twice in 2-3 years it's been up.Pete

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