No Green light on the board

Last Updated OnFebruary 13, 2026

Cause	Solution
No power from transformer (no green light on the transformer)	Check for power at the outlet If power is at the outlet and no green light on the transformer, bad transformer. If green light is on the transformer but no green light on the board, remove transformer from outlet and make sure red and black wire are secured to screws. If yes and still no green light on board then remove cover from the jack and with your volt meter make sure you have 24-28 VAC at the red and black screws. If yes but still no green light on board then you have a bad phone cord from jack to board. Replace cord. Also check wires connected to the battery. Disconnect red and black wires from battery and check those wires for 13.5-14 VDC
Bad Transformer	Replace transformer

Cause

Solution

No power from transformer (no green light on the transformer)

Check for power at the outlet

If power is at the outlet and no green light on the transformer, bad transformer.

If green light is on the transformer but no green light on the board, remove transformer from outlet and make sure red and black wire are secured to screws.

If yes and still no green light on board then remove cover from the jack and with your volt meter make sure you have 24-28 VAC at the red and black screws.

If yes but still no green light on board then you have a bad phone cord from jack to board. Replace cord.

Also check wires connected to the battery. Disconnect red and black wires from battery and check those wires for 13.5-14 VDC

Bad Transformer

Replace transformer