MintyPi 3- Powers from Pi USB but not Power Board

[Prometheum5]

Hi,
I completed my MintyPi 3 build today and have run into an issue. I have successfully assembled and it runs fine when I plug USB power directly to the Pi. Full disclosure I totally housed the first solder attempt and ruined the pads (I know ). I was able to use a fresh Pi and wire it completely to the test pads. Amazingly, it all still fits inside the tin and I think the lid will close.

When I plug USB-C into the power board, the LED lights up green but the Pi will not start. When I connect the battery, the LED turns red. The battery has been sitting for a few months since I ordered it early, and I tested it with my meter and it's all the way dead. I let the system sit charging with the red LED on for a little while but still could not get it to boot. I checked all of the connections on the (updated) power board from this thread: viewtopic.php?p=72903#p72903. Are there any suggestions for what else to check with the power board?
Thanks!

[Helder]

Does the battery have a charge? meaning use the meter to see if it's over 3.7v if it has no charge it isn't going to boot anything. Did you check to see if the black cable connector doesn't have damaged pins from improper insertion like in the Stickied Thread at the top of the forums? Do you have 5V properly soldered and with continuity (check the same thread or wiki for the image)?

Alot of things can be wrong but I gave you some things to investigate, and it's unlikely the power board itself but something you done or are missing (use the questions above as a hint list).

[Prometheum5]

Hi Helder!

Thanks for the helpful reply. I've gone through the steps you suggested and have the following:

Confirmed the battery shows 3.7V power from the hot.
Confirmed continuity between the two 5v GPIO pads on the Pi.
Confirmed 3.7V power from the two GPIO pads on the Pi to the two contacts on the black board (D1 and FB3) as indicated in the Wiki when the Pi is powered through micro-USB on the Pi board.
Confirmed NO 5V power from the GPIO pads to D1 and FB3 when the power board is connected and USB-C power is connected.
Confirmed the black wire power board connector is properly installed and all pins are present.

Not sure what to check next. Thanks!

[Prometheum5]

Just to help provide the most detail, I figured I'd post pics as well and ask one question I thought of. Here's my build.







I've wired everything from the circuit diagram in the build video. Like I said above, it all actually still fits in the tin! I covered the original pads with Kapton tape and abandoned them. My question is, is there a connection needed between the Pi 5V holes and the black board on those two pads even though there's no mention of them in the circuit diagram, other than that they should be bridged? If so, is there a spot on the black board I can pick those up?

Thanks!

Edit- That's totally it, isn't it? I looked at the GPIO pinout and I think I'm not giving the 5v to the Pi board. The two pads on the black board for that are actually still ok, but I don't have confidence in my ability to solder those two thru the Pi holes.

[Prometheum5]

Update- Haven't soldered the two 5V pads down yet because I cannot find the 5V on the main board. I found the 5V coming out the back of the black wire harness connector so the power board seems to be validated. I have good continuity from the two 5V pads on the board to D1, but like 960 Oh to FB3 after trying to reflow the solder there. I've looked at all my wiring solders under a magnifier and don't see any shorts.

Edit- I do have 5V from the back of the white connector to the ground on the black board and on the Pi so my ground is good. I can't get voltage to FB3.

[Helder]

Ok so it's painfully obvious you have no 5v going to the Pi GPIO. You wired all the contacts except the 5v ones, use the image with the 5v test to wire the D1 to the 5v GPIO.

The 5v is what powers the whole kit from battery, you don't have anything wired to those GPIO in the picture.

[Prometheum5]

Ok so it's painfully obvious you have no 5v going to the Pi GPIO. You wired all the contacts except the 5v ones, use the image with the 5v test to wire the D1 to the 5v GPIO.

The 5v is what powers the whole kit from battery, you don't have anything wired to those GPIO in the picture.

It, uh, all works now. I was thinking about it backwards and thought I needed 5V to go from the board INTO the Pi on those two pins so I didn't want to solder the Pi down until I found the voltage. Didn't realize the Pi is making 5V on those pins, found it immediately. All assembled and works now, thank you!

[skeletalpeacock]

Hi,

I am having these exact same issues and symptoms. I can't seem to find the pinout being referred to here for the V3 board.

Of the pins named here that I can id without the pinout, they all meter correctly under continuity and my battery shows 3.83 volts.

At this point, i think i am down to the connection wire. Any ideas?

[Helder]

Hi,

I am having these exact same issues and symptoms. I can't seem to find the pinout being referred to here for the V3 board.

Of the pins named here that I can id without the pinout, they all meter correctly under continuity and my battery shows 3.83 volts.

At this point, i think i am down to the connection wire. Any ideas?

So the stickied thread at the top of this forum was overlooked when you posted here? It's titled "V3 Issues? Check here first!" there is the info mentioned in this thread about solder points and where to test continuity. Go have a read and try the fixes then come back here if they don't work for you.

[santoryu3SS]

so i have all the same problems. i checked for continuity on D1,FB3, and the two GPIO pins for 5v and they all worked.i also checked the connecter cable, and the battery is fully charged.