Page 1 of 2

[Solved]Had it working now it’s not.

Posted: Sun Nov 05, 2017 9:42 pm
by Psyicman
I’m having a problem with one of my MintyPi builds. I had one completely together and it all worked except for the sound. So I moved the power and ground from the PCB pads and soldered them with the main power pads. I plugged it all back together and now all I’m getting is a white screen. I reburned the image and still get the white screen. I’m going to fiddle with it some more and report back but any ideas of what to do would be a big help.

Re: Had it working now it’s not.

Posted: Mon Nov 06, 2017 7:07 am
by rodocop
Check the continuity of all gpio connections. If you moved the pcb out of the tin it isn't out of the ordinary to loose connection on some of the gpios. Any flex of the board can cause that..

Post results of the continuity testing. If everything has continuity then there may be other issues.

Re: Had it working now it’s not.

Posted: Mon Nov 06, 2017 10:39 am
by exodus
I've also noticed that the screen ribbon cable can be very sensitive to the slightest of movements. You want to double check the cable is properly aligned (note my comment is for helder board rev 1)

Re: Had it working now it’s not.

Posted: Mon Nov 06, 2017 6:45 pm
by Psyicman
Yeah I had a feeling I probably flexed something and now I’m paying for it. I’m going to test everything and report back. I am building 3 of them and I was testing a screen and I got no back light on one screen so I’m going to test the voltage and then probably have to do the pin to test pad trick.

Re: Had it working now it’s not.

Posted: Sat Nov 11, 2017 2:46 pm
by Psyicman
So I tested everything and sure enough I had a bad solder joint. I re did the joint rewired the sound to the proper leads and now everything is working fine. Two new problems cropped up on two different Pi's. One was a dim lit screen. I have tried soldering wire to the second pin to the ground test pad but that did not solve the issue so I'm a little at a loss of what to do. The other is on the last Pi it will only power from the secondary usb port. How would I go about solving that issue?

Re: Had it working now it’s not.

Posted: Sat Nov 11, 2017 4:54 pm
by Psyicman
For the dim screen is it possible to just run wires from the test pads on the PCB to the screen PCB test pads? If so can someone post a picture of how it looks please.

Re: Had it working now it’s not.

Posted: Sat Nov 11, 2017 7:03 pm
by Helder
Test the voltage on the LCD pcb using the VCC and GND pads as for your other problems with the other Pi's it's all about your soldering so post pictures so we can have a look for obvious issues.

Re: Had it working now it’s not.

Posted: Sun Nov 12, 2017 12:30 pm
by Psyicman
I tested on the LCD pcb and the voltage read 1.8 volts. The other Pi problem is not really an issue I figured since the power will not be going through the USB port.

Re: Had it working now it’s not.

Posted: Sun Nov 12, 2017 9:26 pm
by Helder
If it's 1.8v then you have a bad ground wire.

Re: Had it working now it’s not.

Posted: Tue Nov 14, 2017 9:21 am
by Psyicman
Yes and I’ve soldered a wire to the pin to the test pad and it is still not working. So I want to solder wires directly to the two PCB boards. Is there a picture of what pads to connect to each other?