My GPIO8 (pin 24 - SPI-CE0) is tied to ground

[ElNorbe96]

Hello, my question is this:
I have a 3.5 "12-pin tft screen, which works by spi, and I was using it without problems on my Raspberry Pi 3b +.
The problem is that suddenly it didn't want to show anything on the screen, it just looked white. I came to believe It was the screen that had been damaged, but I connected it to my Raspberry Pi Zero W and there it works, then the problem is in the Raspberry Pi 3.
With a multimeter I realize that the GPIO 8, which is used by the SPI transmission, is short with ground, I was already measuring continuity on all sides and I removed the solder mask around that pin above and below, but the short continues.
I would like to know if there is any point at which you recommend me check or if the chip or something has already been damaged.
It should be mentioned that the raspberry works correctly in the rest of its functions. I use it from my laptop using VNC and it works without problems.

Thank you very much, regards.

[joan]

With nothing connected to the expansion header run wiringPi's pintest or pigpio's gpiotest.

[pcmanbob]

Using a multi meter to test the continuity may have well been what damaged your gpio pin, any voltage greater that 3.3v will damage the gpio , you meter likely uses a voltage greater than 3.3v for the continuity check.

Most multi meters are powered via 9V battery these days, so you could have as much as 9v on the test probes.