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LED states

Most rusEFI units have four status LEDs.

  • Blue: Communication
  • Red: Fatal/Critical error
  • Green: Engine status on many boards
  • Orange: misc

Some simpler units have only blue and red.

Bootloader

During the bootloader part of the power-on sequence, all four LEDs are expected to blink just to confirm life.

Normal operation

During normal operation, the blue LED is supposed to always blink at 50% duty cycle. The blue LED blinking frequency changes when USB connection is detected. Lack of any blinking means a brand new from factory unit or a completely unexpected firmware condition.

The green LED on many rusEFI boards indicates the engine status.

  • Off: Engine stopped
  • Blinking: Engine cranking
  • On: Engine running

Fatal error

Solid red means critical error; no engine operation is possible and a power cycle is required.

Common Issues

Look at the PCB. On all rusEFI boards we expect the blue LED to always blink.

The Blue LED is not Blinking

Do you have power? Do you have any LED lights? Do you have a USB cable? On all modern units we have a PROG button. Power cycle your unit while connected to PC while holding PROG button, your PC should report STM32 BOOTLOADER in device manager.

The Blue LED is Blinking But Nothing in Device Manager

Make sure your USB cable is a proper data cable, not an evil charge-only cable.