Spa will not power on at all; topside display is completely blank and no pumps run

Safety: This involves line voltage. If you are not comfortable working with 240V circuits, contact a licensed electrician or spa technician. Always turn OFF the main breaker before opening any electrical panel.

• Check GFCI breaker: Locate the spa's GFCI breaker in the main or subpanel. If it is tripped, reset it once. If it trips immediately, there may be a short in the spa or wiring.
• Verify power at spa disconnect: Using a multimeter, confirm that the correct voltage (typically 240V across hot legs and 120V from each hot to neutral, if used) is present at the spa disconnect or junction box.
• Inspect control pack connections: With power OFF, remove the control pack cover. Check that the main power wires are securely fastened to the terminal block and show no signs of overheating or burning.
• Check internal fuses: Many Bullfrog control boards have one or more fuses. Remove and test them with a multimeter for continuity. Replace any blown fuses with the exact same type and rating.
• Restore power and test: After confirming all connections and fuses, restore power and see if the topside display lights up.

If the spa still shows no signs of life with verified power and good fuses, the control pack may have failed and should be replaced by a professional.