Hello, I'm quite new here and I have the following problem:
I have a Pi Model B+ v1.2
The main problem is that the touch sensor on the official 7'' touch screen is not working.
Everything else seems to be working, apt-get update and upgrade installed a lot of things, and everything fine in general.
The touch screen came pre assembled.
I followed the assembly instructions, connected the +5V and GND, and the ribbon cable.
However, I also connected the SCL and SDA lines to GPIO 2 and 3, because I think I was using a tutorial for a regular model B Pi.
Could this have destroyed something? It seems to make no matter if those 2 are conencted or not, everything but touch works.
Anyway, in the course of reading up on the forums, I found out that the red LED is supposed to be on always. Is that correct?
For me it turns on when I plug the Pi in, stays on, while the green one starts flashing, and mid-boot, the red LED turns off and stays off until I shut the Pi down. Once it is shut down, the green LED stops flashing (no more SD activity), and the red comes back on.
I measured the voltage between PP3 and PP7 during booting, and it stays at 5.03 all the time, no drops as far as I can see.
I then unplugged the tiny ribbon cable on the screen, and put it back, to check if that was faulty, but still the same as before, everything but the touch works.
What else can I check?
I have access to a Keithley Sourcemeter, I could use that as a voltage supply, and be then 100% sure that there are no voltage drops. Can I simply connect 5V between the 5V and GND pins?
I looked all over the place for people with similar problems, but all I find is "check the ribbon cable" and "check the power supply"
But those seem not to be it, so I'm at a loss.
I'll appreciate any advice.