Your suggestion did the trick. I first tried to downgrade the LCD to 2.16 – which failed the same way (flashing LCD, no loading of images). However, when I tried to upgrade to LCD 2.17, it loaded the firmware. Here’s the sequence for anyone else having problems.
- Following the instructions in the first link, get access to the SD card slot on the LCD.
- Power off. Insert MicroSD with LCD 2.16 firmware.
- Power on. Firmware 2.16 doesn’t load. LCD screen flashes on and off slowly.
- Power off. Insert MicroSD with LCD 2.17 firmware.
- Power on. Firmware 2.17 loads. LCD shows the images loading. Wait for LCD to go blank
- Power off. Remove MicroSD card.
- Power on. Look for the new bed leveling function to confirm 2.17 loaded.