Safety first: Verify that the circuit breaker is off before opening the oven. High voltage is present inside.

Steps to diagnose:

Check external supply: Confirm that the wall outlet or circuit is live and that the breaker has not tripped.
Inspect terminal block: Remove the rear cover and check for loose or burnt connections at the mains terminal block. Tighten or replace as needed.
Check internal fuse: Many OBH Nordica ovens have an internal fuse on or near the control board. Inspect and test the fuse; replace only with the same type and rating if blown.
Inspect line filter: Examine the EMI line filter for burn marks or open connections. Replace if faulty.
Control board power supply: If mains power reaches the board but there is no low-voltage output, the power supply section of the PCB is likely defective. Replace the main control board.
Test: After repairs, restore power and verify that the display and controls function normally.

Oven display and controls are completely dead; no lights or response.

Possible Causes