Current ranger Won't Turn Off [drenched in flux residue....]

Started by Farmbot26, September 07, 2020, 03:07:14 PM

Farmbot26

The second I plug in my LiPo battery the unit powers up, without touching the power button. I can't turn it off with the power button. After ten minutes it plays the alarm and reboots. The unit seems to function as it should while it's on. Can anyone help diagnose this?

Felix

Can you check the power button terminals with your DMM's continuity function?
What is the voltage on the lipo battery?
Take a close look at the SMD components near the battery terminal, are any damaged/dislodged?

Farmbot26

Button is about 1kOhm when unpressed and 0.2 when pressed. No SMDs seem damaged or missing. Battery is 3.9V.

Felix

And this has happened the very first time you tried to power the CR?
Was this purchased from LowPowerLab or WELECTRON(Germany)?

Farmbot26

Correct and I purchased it from here. I can send you the invoice and such if that would help somehow

Felix

No need for an invoice. Not sure how else to debug that, maybe there is something to learn from this. It could perhaps be a wrong component placed on the board that causes the ON/OFF circuit to behave like that although all units are tested in various ways and they are turned ON/OFF and such a fault would be obvious right away.
I will offer to take a look at it and determine it was shipped defective and repair/exchange the unit. You would however need to return it. If that's acceptable to you please contact me at felix at lowpowerlab dot com for details.

Felix

As a follow up. Take a look at the returned CR.
I wouldn't normally even touch anything like this. In fact this turns ON and OFF and keeps OFF but the OFF only happens when the button is released.
Looking at the residue left behind from soldering or whatever in the world happened on the SMD side ... I am surprised this CR even works at all. Anyway a quick cleanup and it works just fine.

Anyway I can't spend my time doing cleanups and debugs of unknown events, this is not how I delivered any board. Normally if the fault was present out of the box then we would have something to talk about. That is why I test everything and ensure faults like you reported do not ship. So I at least expect people to send me a board that is in new or near new condition and not soldered and drenched in flux residue, if there is any claim of a fault.

This is no fault, the CR will be returned.