Micro Dot pHat help

I am a newbie to soldering, but I believe that everything should be good to go. It doesn’t seem like I have anything crossed and have soldered all of the connection. When I plug in the hat to the GPIO pins I basically lose access to my RPi4. The HDMI output of the display shows nothing. I cannot VNC into the pi or ssh to access the terminal either. When I unplug the micro dot phat and restart, everything is fine and I get display with access to vnc and ssh.

I am wondering if you have any guidance and if I need to change some settings on my pi to get access while the phat is plug in. I am also starting to think that I the phat may be screwed up on some way. I have followed the startup instructions to the best of my ability and have downloaded the associated python files/commands and enabled i2c.

Please help!!

Photo of back since I can only upload one image per post

I see some issues with the soldering. Too many iffy ones to point them all out.
I’m not meaning to demean you etc, just commenting on what I see. I’m a retired electronic technician if it helps. The pins used on the GPIO are listed here


When you power up does the red power LED light up? Note there won’t be a RED LED if its a Pi Zero. Does the green status LED flicker?

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soldering101

https://learn.pimoroni.com/tutorial/sandyj/the-ultimate-guide-to-soldering

I will review the guide and do my best to go through and clean up the connections

I see the pins used on the GPIO but what does that really mean? Should I not be connecting all of the pins or do I need to change something in the software of the RPi4.

When I have the pHat plugged in and power on the red and green lights on the Raspberry Pi 4 stay lit steady. Additionally, there is no output to the connected hdmi. It seems to be hung up on startup.

The GPIO pinout just shows what’s used by that pHat. That can be relevant some times when trying to find an issue.
You could have just soldered the ones used, and a few more for stability. Me personally, I solder all of them.
I don’t know 100% why it won’t boot, but best guess is you have one or more pins on the phat shorted to one another. On the plus side it looks like you haven’t damaged the Pi. It’s still likely not good for it.