SparkFun Troubleshooting Tips
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SparkFun Troubleshooting Checklist
Regardless of our level of experience, failure rates can be reduced and issues can sometimes be resolved faster by having a checklist. Here is a list of questions to ask yourself when troubleshooting your project:
Hardware Checks
Check Your Connections
▢ Is there continuity between the pins, and is the connection secure?
▢ Are there shorts?
▢ Is the wire or cable bad?
▢ Where did you get the USB cable?
▢ Was the component connected using the correct polarity?
▢ Did you use the basic hookup?
▢ Are your solder joints ideal and making a sufficient connection?
▢ Are there solder jumpers connecting pins where they should?
▢ Is there water-soluble flux residue on the boards?
Length of Wire
▢ Are you using extra long wires?
▢ Have you tried using a different computer?
▢ Is there a problem with the USB Hub or USB port that you are using?
Check Your Logic Levels
▢ Can you connect a 3.3V sensor to a 5V board?
Stacking Multiple Boards
▢ Are you stacking more than one board (e.g., Arduino shield, Raspberry Pi HAT, Beaglebone Cape, etc.) together on top of your development board?
Check Your Location for Interference
▢ Is the component not working in a particular room or building?
Power Supply
▢ Is your power supply sufficient?
▢ Does your Arduino stop working every time your motor starts up?
▢ Does your project work with a power supply connected to a wall outlet but not with a 9V battery?
Power Cycle
▢ Was your project working fine when connected to the wall outlet for a few months, but is now not working as expected?
Heat Dissipation
▢ Is your motor driver getting hot to the touch? Is this normal?
Electrostatic Discharge (ESD)
▢ Did you ground yourself before touching the device?
Limitations of the Product
▢ Are you using the component as expected?
Wireless
▢ Will your wireless device not connect to the wireless network?
▢ Will your wireless device not work inside of a metal enclosure?
Software Checks
FTDI Drivers
▢ Did you install the FTDI drivers?
▢ How can you tell if you have the FTDI drivers installed?
▢ How can you tell if your FTDI is sending serial data?
Arduino IDE Versions
▢ Is there something wrong with your Arduino IDE?
Board Selection
▢ Did you select the correct board definition?
COM Port Selection
▢ Did you select the correct COM port?
Installed Arduino Libraries
▢ Does your example code require libraries to be installed?
▢ You installed the necessary Arduino libraries, so why is it still not compiling?
Corrupt Bootloader or Bricked Arduino
▢ How do you recover your Arduino if the bootloader is corrupt?
▢ Your Arduino with ATmega32U4 stopped working after uploading new code. What happened to the ATmega32U4-based microcontroller?