Easy Raspberry basics: Project 01b Troubleshooting of common hardware Raspberry Pi problems

of Acoptex.com in Raspberry Pi 3

Raspberry basics: Project 01b

Project name: Troubleshooting of common hardware Raspberry Pi problems

Tags: Raspberry, Raspberry PI 3 model B board, common hardware Raspberry Pi problems, troubleshooting

Raspberry Pi
Monitor or TV
HDMI cable
USB keyboard
USB mouse
Power supply
8GB SD card


This article about the common hardware problems for any Raspberry Pi user and what to do when they occur.

Let's start to check them together. 

  1. The green LED flashes and nothing is on screen. This is most common problem. It’s likely a boot failure - a blank SD card or a lack of correct data on the SD card causing that. Check that your SD card is fully inserted. With the latest Raspberry Pi firmware, if you have: 3 flashes – start.elf is missing, 4 flashes – start.elf not launched, 7 flashes – kernel.img not found,  8 flashes - SDRAM not recognized (SDRAM is probably damaged, or the bootcode.bin orstart.elf cannot be read). Status lights meaning: OK/ACT- Green - SD card activity, PWR-Red- Power, FDX-Green-Full Duplex (LAN) connected, LNK-Green-Link/Activity (LAN), 10M/100 - Yellow -100Mbit (LAN) connected.
  2. Raspberry Pi shuts down or restarts randomly. Power issues can cause a Raspberry Pi to fail. It might switch off or hang when running, or it might simply fail to boot at all. Swap out the cable. If you’re still having problems, swap out the power supply. A stable power supply required for the SD card to be reliably read. Check that your power supply meets the specification of your particular Raspberry Pi model. A lot of people use smartphone chargers to power a Raspberry Pi. It's not a good idea; a dedicated, suitable power supply is the preferred approach. The Raspberry Pi has a resettable fuse. This polyfuse can reset itself, but it can take up to a couple of days. If you have accidentally blown the polyfuse, you’ll only find out when you try booting later on. If your Rasperry Pi is overclocked, it’s also worth using the raspi-config tool to set it back to defaults. You may just be overheating it. If setting it to default clock speeds helps, increase again gradually until you find something stable.
  3. I can’t see my USB hard drive. This is another common problem caused by using a non-powered portable USB hard drive in a non-powered USB hub. The easiest way to fix this is to power one side or the other. If using a portable, USB-powered hard drive, you should really use a powered USB hub. If you definitely have power, the hard drive could be in an unreadable format. Try using FAT32.
  4. No Video Output? Your Raspberry Pi cannot display any video without an SD card present. There is no on-board BIOS, so there’s no way anything can be displayed. Therefore, you need to ensure that you’re using a reliable, working HDMI cable. Meanwhile, the Pi itself needs to detect the display. Similarly, the display device needs to be capable of detecting the signal from the Raspberry Pi. If the Pi appears to be failing to boot because nothing appears on screen, you’ll need to force HDMI detection. You can do this on your computer by inserting the SD card, and browsing to the /boot/ partition. Open the config.txt file, and add the following to the end: hdmi_force_hotplug=1 . Save and exit the file, safely remove the SD card, return it to your Raspberry Pi, then try to power up again. If you’re using NOOBS with the aim of installing an operating system on your Raspberry Pi, and nothing appears on the display, you can try some keyboard shortcuts. Within the first ten seconds of booting, tapping 1, 2, 3, and 4 on your keyboard will force the display output signal to switch between ideal HDMI, safe HDMI, PAL composite, and NTSC composite. Some Pi models use TRRS, which means you need the correct cable, one capable of translating the RCA (red and white connectors) and composite (yellow connector) signals.
  5. The HDMI image from the Raspberry Pi has noise. If the picture from your Raspberry Pi is noisy (screen is shaking, dots or green lines, etc, moving around) then it’s probably a dirty connection. Make sure the HDMI or composite cable is connected properly, clean (free from dust and other contaminants). If you still have a problem, try another HDMI cable. You can also try adding the following to your SD card’s config.txt: config_hdmi_boost=4

  6. Ethernet stops working with some USB devices. Check that your power supply is working. It has been known for some power supplies to provide an inadequate source of power. Try changing out your cable (it may just be a bad cable). Also, try the failing device in a powered USB hub – rather than plugging it directly into the Raspberry Pi. Ethernet socket status LEDs: 10M/100 - Yellow -100Mbit (LAN) connected, LNK - Green - Link/Activity (LAN).
  7. Red power LED is on, nothing on display. In the normal status both PWR and ACT LEDs activated. ACT will flash during SD card activity, while PWR will be always on (blinks when power drops below 4.65V). Check the power cable is properly seated. Check that your SD card has a valid image on it. Can you still read the SD card in the PC that the image was created on? If you can, try booting your Raspberry Pi with just the power supply connected. Watch whether the 'OK/ACT' light flashes. If it does, add the cables back in one by one. Status lights meaning: OK/ACT - Green - SD card activity, PWR-Red- Power, FDX-Green-Full Duplex (LAN) connected, LNK-Green-Link/Activity (LAN), 10M/100 - Yellow -100Mbit (LAN) connected.
  8. Raspberry Pi doesn’t boot.  This is likely to either be a bad mount of an SD card or a power supply issue. Check your SD card: it may well be that it’s not seated correctly. Take it out and put it back in straight – and make sure it goes in all the way it possibly can. If it was definitely in correctly, try cleaning the contacts and restarting to see if it works. If this fails, try another power supply to see if it works there.
  9. I broke a part off. If the part that broke off happens to be a silver cylindrical piece near the Raspberry Pi’s power input, this is easy enough to fix – this has been broken off by many other people due to its large surface/small mount area. This piece of the Raspberry Pi reduces noise and stops power spikes. You can either reattach it (depending on your soldering skills), but you can use the Raspberry Pi just fine without it – with most power supplies.
  10. Dead or Defective Raspberry Pi? If you’ve got this far with no results, then there is a chance that your Raspberry Pi is defective. For a Raspberry Pi B, B+, 2B, 3B, or 3B+ the only way to work out if it is broken is to have an identical model to hand, one that you know is working. From the suspect device, remove the SD card and anything that is connected -substitute the working device with the same cables, peripherals, and SD card. If the device boots, your other Raspberry Pi is faulty; if not, then your cables, power supply, or SD card are causing the problem. For Raspberry Pi A, A+, and Zero devices, there is different way to check suspect devices. Remove all cables, and the SD card, and connect the device via USB cable to your Windows PC (USB-A to USB-A for the Raspberry Pi A and A+, micro-USB to USB-A for the Pi Zero models). If working, the device will be detected, and an alert will sound, and you’ll find the Raspberry Pi listed in Device Manager. On Linux and Mac, you’ll find a working Raspberry Pi A or Zero listed in response to the dmesg command in the terminal.


We have learnt about the common hardware problems with Raspberry Pi and what to do when they occur.


  • No libraries needed in this project


  • No sketches needed in this project

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Published at 05-04-2019
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