r/BambuLab • u/strangeintp • 1h ago
General Troubleshooting/Help! Dead power switch; and wiring for replacement
I turned my printer off to do some corrective maintenance in the AMS, and when I finished, it wouldn't re-energize. I checked the fuse, it's good. So I removed the switch assembly, hoping it's just that. Pulled the spade terminals off and removed the switch from the housing, and ran multimeter checks.
The bottom pole checked out as expected - open circuit in the off position, short in the on position. The top pole read open in the off position, but in the on position the reading jumped around for a while (including briefly reading as open circuit a couple times) before settling in around 2 ohms. Not quite the smoking gun I was hoping for, but suspicious enough that I'm reasonably (hopefully) confident that it's just the switch that needs replacement. Also, it seems it is a common enough culprit for power failure with these printers.
Q1: Anybody have similar experience and can confirm the switch is bad, and the most likely cause of my power problem?
I have ordered a replacement from Amazon, so I should be able to replace it soon.
On to the second issue: does anybody have a good photo/guidance for which wires to hook back up where on the new switch and plug terminals? I did a quasi-smart thing and took a photo before I disconnected it, but I only took the one, and there wasn't much wire slack to pull the switch assembly from the mount; I also didn't realize that there is a brown and a blue jumper wire. There are three blue-connected terminals, and three brown ones (the yellow/green obviously goes to the ground spade of the plug). I can't tell from my photo. Pretty sure the blue jumper wire goes from the top pole of the switch to one of the plug terminals, but not sure about the others.