L1 or L2-Phase Open Error

What does 04 mean?

An open circuit is detected in either the L1 or L2 phase of the main power input, indicating a missing power phase. This typically prevents the power circuit board from receiving a complete supply, leading to system shutdown or malfunction.

• Open circuit detected on the L1 or L2 power phase.
• Blown fuse or tripped breaker on the respective phase.
• Loose or broken wire on the L1 or L2 power input.
• Fault in the power distribution.

Click steps to track your progress.

1. 1

   Measure the voltage at the L1, L2 (and L3 if applicable) input terminals to verify all phases are present and at nominal voltage.

2. 2

   Check the main power breaker and fuses for the L1 and L2 phases for trips or blows.

3. 3

   Inspect the wiring connections from the main power supply to the power circuit board for looseness or disconnection.

4. 4

   Inspect the power circuit board for any visible damage.