Hi Richard and welcome to the site, I’m Louie. Sorry you had to wait awhile but I’ll do my best to help.
Initially, bear with us; re-confirm and post back with the complete model number of the phone system.
As requested above; what is the complete model number of the phone system ?
Please post back with the "...4 Model Numbers on the instruction booklet..."
Appreciate the additional information.
Thank you for allowing me time to review the documents and compose my reply.
A little more background info please:
The model would be KX-TG4112C where the last digit indicates the number of handsets.
Please check if any of the handsets shows an icon of a bell with a diagonal line through it.
That bell icon with a diagonal line indicates that the ringer has been silenced.
The ECO would pertain to economy mode; i.e. battery life.
Can we try adjusting the ringer ?
Main MENU / Initial Setting / Sub-menu 1 (Ringer Setting) / Sub-menu 2 (Ringer volume) / set 0 - 6
Or hopefully simpler yet, dial # 1 6 0 then select ringer volume preferred.
Use ▲/▼ to select preferred volume level.
Then SAVE, THEN OFF
number of the screen ?
Let's try again please using the handset:
Sorry but no.
That would mean that that the phone is not in the correct menu/sub-menu.
Were you able to press the MENU button (middle button) before pressing the # 1 6 0?
...and the ringer is back on now?
Can you try using your cellphone to call your landline/home number?
Can you please try pressing OFF on the handsets?
Still, please see p. 16 and 22 of the instruction booklet.
Post back an update when able.
Pressing the OFF button causes a message to be displayed?