It seems that the problem,with the SDA pin, is on the LCD side. I can't see anything in the photos that would explain that.
Do you have a DMM to measure the resistance between THE ground and the SDA pins on the I2C connector on the I2C backpack?
It seems that the problem,with the SDA pin, is on the LCD side. I can't see anything in the photos that would explain that.
Do you have a DMM to measure the resistance between THE ground and the SDA pins on the I2C connector on the I2C backpack?