Brymen BM257s: Current function stopped working suddenly; blank display

[xraj]

Just wanted to relay my experience in case anyone else experiences something similar. The meter is about two years old with very light usage. It was bought off ebay (99centhobbies) in 2015.

Today after measuring small currents in the 1A range, I turned off the meter. A few hours later, I turned it back on to the A function, and the display was blank. Turning it back to any other function, and the display would work normally. Turning it back to either of the current function and the display would go off. Long pressing any of the buttons would cause a beep, so it wasn't simply turning off.

I found this older thread about calibration errors:

https://www.eevblog.com/forum/testgear/brymen-257s-lost-calibration-data/

In desperation, I followed the procedure there to enter calibration mode. Simply entering calibration mode, exiting and turning it off seems to have "fixed" it, because the current function now works again.

I've also found that I can cause it to reset by pressing on the selector knob along the edge. I don't know if that's causing a fault or it's just losing power due to bad contact.

I sent an email to Brymen support. We'll see what they say.

[xraj]

Support got back to me.

Apparently the calibration mode trick wasn't so crazy after all. He suggested that it had lost calibration and gave me the same directions for putting it in calibration mode and turning it off.

[SkyMaster]

Thank you for sharing your experience with us.

I never had any problem with any of my Brymen multimeters, but you never know.