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BLTouch Failing M48 Test

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  • BLTouch Failing M48 Test

    In the past few days I had a problem with my new BLTouch. It stopped leveling the bed partway through. I would start a print, the axes would home (including the Z), then it would start the 9 point bed level. At point 2 or 3 it would start firing the probe up & down repeatedly and then the LCD would display STOPPED.

    I looked at a number of things, but the fact that it just started out of the blue made me suspicious it was a hardware issue. After checking other things, like reseating the Z axis limit switch connection on the control board, I homed in on the connector to the BLTouch sensor. Here's a photo:

    Click image for larger version

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    The thing to notice is the white & blue wire connectors. I had noticed that both of these connectors were exposed when I 1st got the BLTouch, but, because both end connectors looked much the same, I assumed this is the way it's supposed to look. And, the BLTouch worked, which reinforced the idea that all was well. It isn't.

    I used to have 20/5 vision in my left eye & 20/10 in my right so, decades ago, I would certainly have noticed that there are 5 wires but only 4 little plastic 'retainers'. Since I'm now developing cataracts, and need reading glasses most of the time, I didn't notice it until looking at the photo. I did not do this: the cable was like this when I got the package.

    In any case, closeup inspection revealed that the white wire's connector was not making good contact with the sensor -- it had worked loose after a number of prints. I very carefully reseated the connector, paying special attention to getting the white wire fully connected.

    I looked on Amazon to find a kit of JST connectors the same size as the existing 1. I believe it's a 1.25mm or 1.5mm, but I'm not certain, and I haven't been able find a spec sheet that shows it. Also, I could only find 1.5mm connectors on Amazon. I guess I could order the 1.5mm kit and return it if it doesn't fit, but I don't like abusing Amazon's return priviledges. I guess another option would be to use hot glue to anchor the wires in place.

    I will look in my trove of spare wires & parts to see if I already have the right connector.

    ​​​​​​​Returning the BLTouch isn't really an option because I ordered it off AliExpress..... it would take forever to get a new cable.
    Last edited by Ender5r; 12-23-2020, 03:57 PM.

  • #2
    Ender5Pro The photo did not show up in your post.


    • #3
      Hope it's there now.


      • #4
        Originally posted by Ender5r View Post
        Hope it's there now.
        Yep it is. Yea white pin tab is broken off will let pin slip up. not good


        • #5
          I will likely have to use hot glue. I checked my stock of spare cables/connectors. I have 4-pin & 6-pin of the right size, but no 5-pin 😫😪


          • #6
            I sympathize with Ender5r for his cataract problem. 21 years ago when I got hit by lightning I got cataracts in both eyes but the left eye formed super fast so that I was blind in my left eye and could see a yellow tinge in my right. I was relieved when that was removed and I could see again. The right one seems to have faded away over the years.