After swapping SD cards to try out a fresh install my Pi 3B+ will not boot from either the original (working) SD or the newer SD which I've just flashed the latest image onto using Etcher.
It doesn't matter whether there is an SD card present or not, the red power light comes on but the green ACT light does nothing.
I have the official power cable, which has worked perfectly all along even when also powering external USB drives. I have tested the Pi with two other power sources also, and have the same thing. Since reading the sticky post this morning I feel confident that it couldn't be a power issue anyway because the red light comes on and stays on.
I have reflashed the image again using Etcher and still nothing.
At the weekend I am going to borrow a friend's Pi and test my SD cards in that.
Does anyone have any suggestions in the mean time?