# RPi 4B cactus? **URL:** \ **Category:** Raspberry Pi\ **Created:** [18 December 2025 07:16 UTC](https://forum.core-electronics.com.au/t/rpi-4b-cactus/23723 "2025-12-18T07:16:22Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Toni135859](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Toni135859](https://forum.core-electronics.com.au/u/Toni135859)\ **Post date:** [18 December 2025 07:16 UTC](https://forum.core-electronics.com.au/t/rpi-4b-cactus/23723/1 "2025-12-18T07:16:22Z")
After good service my Pi4B has stopped working. I downloaded the latest operating system which works perfectly on a Pi3 but not on the Pi4. With the card inserted into the Pi4 and power turned on the green led stays on and solid. Any suggestions please. Is my Pi4 cactus? Toni ---
**Author:** ![Jane](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/jane/32/12622_2.png) [@Jane](https://forum.core-electronics.com.au/u/Jane)\ **Post date:** [19 December 2025 03:12 UTC](https://forum.core-electronics.com.au/t/rpi-4b-cactus/23723/2 "2025-12-19T03:12:31Z")
Hey there, Toni, A couple of things to ask before we cactise it: - Are you still getting HDMI output on the Pi? - If yes to the above, with no boot media inserted, are you coming to a Boot menu screen? - Can you boot from another SD card? - Can you boot from USB even if SD is not working? ---
**Author:** ![Toni135859](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Toni135859](https://forum.core-electronics.com.au/u/Toni135859)\ **Post date:** [19 December 2025 21:57 UTC](https://forum.core-electronics.com.au/t/rpi-4b-cactus/23723/3 "2025-12-19T21:57:47Z")
Hi Jane, Thanks for the questions. Results as follows: Yes, still getting HDMI (box) messages on Raspberry Pi screen. With no card installed HDMI fires up and moves to ‘trying boot mode’ and following the esc prompt at the bottom of that screen I get a diagnostic text message which includes ‘boot loader … failed’ every 25 seconds With new card installed (created with Raspberry Pi Imager) HDMI text box fires up, followed by a multi-coloured screen which instantly changes to a flashing ‘-’ prompt on a blank screen. This response repeats continuously. With a card which works perfectly on a Pi3B I get a ‘Welcome to RaspberryPi desktop’ screen which then disappears and the cycle repeats. Does this make any sense? PS I love the verb conjugation of cactus!! ---
**Author:** ![Jane](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/jane/32/12622_2.png) [@Jane](https://forum.core-electronics.com.au/u/Jane)\ **Post date:** [22 December 2025 00:20 UTC](https://forum.core-electronics.com.au/t/rpi-4b-cactus/23723/4 "2025-12-22T00:20:59Z")
Thanks for that, @Toni135859, It sounds like its boot cycling when any SD Card is installed. In addition to trying to boot it from the USB (so we can rule out if the SD Card is the problem) could you please follow the steps in the below to update the Pi 4’s Bootloader. It’s possible the eeprom on the board has become corrupted. > **[Updating the Bootloader on the Raspberry Pi](https://pimylifeup.com/raspberry-pi-bootloader/)** > > Get the latest fixes and improvements ---
**Author:** ![Toni135859](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Toni135859](https://forum.core-electronics.com.au/u/Toni135859)\ **Post date:** [22 December 2025 01:01 UTC](https://forum.core-electronics.com.au/t/rpi-4b-cactus/23723/5 "2025-12-22T01:01:17Z")
Thanks Jane , I’ll give it ago but I may not get back to you until after Christmas Toni ---
**Author:** ![Jane](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/jane/32/12622_2.png) [@Jane](https://forum.core-electronics.com.au/u/Jane)\ **Post date:** [22 December 2025 02:49 UTC](https://forum.core-electronics.com.au/t/rpi-4b-cactus/23723/6 "2025-12-22T02:49:34Z")
No worries, @Toni135859, Come back to us when you can and enjoy some Christmas Cheer. ---
**Author:** ![Toni135859](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Toni135859](https://forum.core-electronics.com.au/u/Toni135859)\ **Post date:** [11 January 2026 06:46 UTC](https://forum.core-electronics.com.au/t/rpi-4b-cactus/23723/7 "2026-01-11T06:46:16Z")
Hi Jane, Thanks for the referral to the great article. The problem was with the boot loader! All fixed. Cheers Toni ---
**Author:** ![Jane](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/jane/32/12622_2.png) [@Jane](https://forum.core-electronics.com.au/u/Jane)\ **Post date:** [11 January 2026 23:24 UTC](https://forum.core-electronics.com.au/t/rpi-4b-cactus/23723/8 "2026-01-11T23:24:24Z")
That’s so great to hear, @Toni135859, I’m so glad everything’s up and working well again. Have a wonderful 2026.