Pi 4 boot fails at rainbow screen

[timg11]

I have a Pi 4 that was freshly configured with 2019-09-26-raspbian-buster a few months ago. It was properly shut down in a working state and has been sitting unpowered and untouched. Now I power it up, and the boot freezes at the rainbow screen.

The Red LED is on. The green LED does the normal intermittent flickering pattern as it starts booting. There is one long green flash, then the rainbow screen appears on HDMI, and the green LED never blinks again. The rainbow screen never changes.

powering up without SD-card produces the expected 4 flashes. Examining the SD-card in another computer shows the boot files are intact and look normal.

I've read the sticky post on boot issues, and didn't find this case covered. Is there any additional guidance?


Edit: I tried the bootloader fix:

Code: Select all

    Download the bootloader
    SHA-256: 444e0f68aa21d5b4e158259061de55738d36a1986e2ced14bb14d7af1a04881c
    Extract it to an empty FAT-formatted SD card and insert it into your Raspberry Pi 4
    Connect the power and wait for the green LED to flash quickly

It succeeded, and I saw the fast green LED flash. However, the Pi still has the same boot failure as above.
Note - the instructions above say "FAT" formatted, but that is not an option. Only FAT32 and NTFS are available in Windows 10.
I'm assuming that FAT32 is also supported since the processed ended with a fast green LED flash, but I could be wrong.

[Setchiel]

I have this exact same problem. I get nothing but a full rainbow screen? I too downloaded and ran the boot loader in an attempt to resolve.

Hardware
Micro SDXC card is 64 GB and is formatted to FAT32.
Raspberry pi 4 Model B 4GB RAM
Case Micro Connectors acrylic stackable
Power supply Micro Connectors model XS-0503000S output 5V 3000mA With USB-C

Software
NOOBS_v3_3_1.zip unzipped to formatted to FAT32 SDXC (defaults, os, overlays in folders but rest are root screen)

Put the SD card in Pi, plugged in monitor, keyboard, mouse and power. Powered on to see rainbow screen. Help please....

[timg11]

Hi,

Given the lack of response, I'm assuming there is no known process to fix this.
I reformatted the SD-Card and started again. Back up an running, but of course substantial wasted time.

I imaged the SD this time after initial configuration.

If it happens again, I'll have to conclude a defective SD-Card.

[FTrevorGowen]

Hi,

Given the lack of response, I'm assuming there is no known process to fix this.
I reformatted the SD-Card and started again. Back up an running, but of course substantial wasted time.

I imaged the SD this time after initial configuration.

If it happens again, I'll have to conclude a defective SD-Card.

"Patience is a Virtue" - all contributors to this forum do so voluntarily and until someone who has (or has had) a similar problem visits you will not get a response. SDXC cards are known to be "trickier" especially as, unless they're specifically labelled as such, card slots on laptops may not be fully compatible. (Historically this occurred with SDHC cards too, both formats, and associated hardware, being rolled out in cameras first - the only devices I have, for example, marked SDXC compatible being a camera and a couple of USB-based card readers).
Trev.

[badi.varaee]

Hi there,
I have the same problem. I even flashed the SD card again and tried to boot the raspberry pi 4, but it does not work. First, It was working fine but after we swap the power supply (5V, 3A) and the screen, both Raspberry Pis did not come up again. How we can be sure that they are still working? how can I reset the hardware? I even install the Raspberry pi image but still did not come up on that raspberry pi. What should I do?
Is there a simple way to reset the raspberry pi hardware?
Regards,
Badi'