Forcing the K3 into "Firmware Load Required" Mode

To force the K3 into a state that it requires a firmware download,

• Disconnect (unplug) the K3 from its power supply for at least 30 seconds. The microcontroller may continue to function with as little as 1 volt, capacitors take a while to discharge, the current draw is quite low, and the MCU must perform a power-on reset to enter its bootstrap loader. If you encounter difficulty getting the K3 to respond to the K3 Utility, try increasing the time the K3 is disconnected from its power supply. Installation of the KPA3 12V Sense Modification reduces the time period required.
• Click "Close Port" on the K3 Utility Port page.
• Reconnect the power supply.
• Press and hold the K3 Power button for about 10 seconds until the red TX LED under the Power button begins to blink and "MCU LD" appears in the LCD display. The LCD back light may be off.
• Click "Test Communications" on the Port page. You should see a status message indicating that the K3 is ready for MCU firmware load and is communicating at 38,400 bps.
  
• Click "Send All Firmware" on the Firmware page.