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:

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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.

@Ender5Pro The photo did not show up in your post.

Hope it’s there now.

Yep it is. Yea white pin tab is broken off will let pin slip up. not good

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 [SIZE=20px]??[/SIZE]

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.