I picked up one of those usb c di2 charger adapters from RRSKIT, battery was at 40% something. After leaving it 30 minutes to charge on a known good USB A to C cable, the etube app asks if i want to connect to previously connected unit, and shows "there is no battery, or the battery does not have a sufficient charge. use a battery with sufficient charge, or charge and then reconnect the battery". RD button doesnt activate the LED at all

Any idea??

Solved. Apparently using a good usb cable is a bad thing. Do not use a high performing cable because that triggers the BMS to shut down the battery. Using a low voltage cable worked perfectly fine. My apologies to rrskit for the many millions in damages my skepticism caused

Quote from: kbernstein on August 27, 2026, 10:30:27 AM
Solved. Apparently using a good usb cable is a bad thing. Do not use a high performing cable because that triggers the BMS to shut down the battery. Using a low voltage cable worked perfectly fine. My apologies to rrskit for the many millions in damages my skepticism caused

I always use shitty USB-C cables that come with many of the shit I've ordered from Aliexpress, so I guess I am safe haha.

wait, what? What even qualifies as a 'bad' cable lol

I just ordered one of these adapters together with the button thingy

Aren't they all 5V unless it's power delivery? I guess an old USB2.0 extension cord would limit it to 0.8-1 amps..?

the diameter of the cable gives you the difference between good and bad cable

I always use "bad " cable for small applications

Quote from: FrostedDyslexia on August 31, 2026, 09:13:39 AM
wait, what? What even qualifies as a 'bad' cable lol

I just ordered one of these adapters together with the button thingy

Aren't they all 5V unless it's power delivery? I guess an old USB2.0 extension cord would limit it to 0.8-1 amps..?

USB-C is a mess. The EU forced a standard, which was a great idea. But different devices use different things, and it gets extremely confusing. There's wattage / voltage questions, and then there's also data/no data, and how both sides of the cable communicate.
I think the result is that we now have 1 port for everything, but we still all need lots of different cables and chargers... I also have battery packs that stopped working with newer phones, because the chip on the phone stopped recognizing "dumb" power, even if it's powerful enough.
The whole thing is a confusing mess.

I got a p2r helmet, the USB rear light says not to use USB pd, just 5v USB not to damage the light.

Using an old 2.0a charger with USB a to USB c cable probably is the safest option.

I have used that di2 adapdor with an old powerbank (without quick charge) a couple of times without any issue.