How do you troubleshoot a PIC® device that runs in debug mode but not in normal mode?

Here are some suggestions to troubleshoot a system that does not run by itself, but works when driven by a debugger:

  1. MCLR low causing the PIC® device to be held in reset or a latch-up condition where the PIC device wasn't powered up properly according to the VDD specifications.
  2. Check the internal oscillator on the CLKOUT pin to see if it is running.
  3. Test a simple program toggling a pin, perhaps a different pin, and see if this works in the same setup.
© 2025 Microchip Technology, Inc.
Notice: ARM and Cortex are the registered trademarks of ARM Limited in the EU and other countries.
Information contained on this site regarding device applications and the like is provided only for your convenience and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of Microchip devices in life support and/or safety applications is entirely at the buyer's risk, and the buyer agrees to defend, indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights.