All Raspberry Pis are tested before they leave the factory in Wales, so a faulty Raspberry Pi is quite rare!
Below are the most common reasons for a Raspberry Pi 4 not to work as expected.
- Wrong HDMI port - The Raspberry Pi 4 has two HDMI ports (seen below). The connector on the left marked "HDMI0" is the primary display, so you'll need to ensure this one is always plugged in.
- Operating System - Only the latest operating system release will work on the new Raspberry Pi 4. This will also need to be a fresh install, not one used with a previous model of Raspberry Pi. Your options are..
- Power Supply - The new Raspberry Pi 4 needs more power than previous models - we only recommend the official 5.1V 3A power supply
- Re-seat your SD card: If your SD card isn't quite pushed in properly, the Raspberry Pi may show some lights but it won't be working properly. Remove power, take the SD card out, push it back in and try again.
- SD Card quality - Unfortunately cheap and 'No name' SD cards are a false economy. The Raspberry Pi forums show many posts with troubled users having issues with their poor quality SD cards. We recommend Panasonic/Sandisk micro-SD cards for the Raspberry Pi - other cards can cause endless issues.
- Corrupted SD Card - Sometimes SD cards corrupt no matter how careful you are. You might spot this if your Pi 4 doesn't boot but you see 8 flashes on the LEDs.
If you have a micro-SD card reader it takes just a few clicks to reflash the card using Raspberry Pi's imager software on a PC/laptop: https://www.raspberrypi.org/software/
- Check the Indication LEDs - the Raspberry Pi indication LEDs can tell you a lot about what is happening with your Raspberry Pi. There's a comprehensive Raspberry Pi forum post on this subject which will assist you, with a Pi 4 specific section here.
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