All of the lines are steady red, which means the
You need to find where your phone line has a problem. This could be a sign of a wiring problem inside or outside or a problem with the phone itself. First try another phone at the current jack (I prefer to use an old corded phone with a different phone wire). Since this is a 4-line phone, you will need to check each line separately. Check for dial tone. If the test phone works, try the second wire with the ATT-974. If it still doesn't work, replace the phone. Modern phones aren't meant to be user fixable. If neither phone works, continue below.
Next try both phones at a different jack. If the phones both work and the jack is for the same line as one of the lines to the first jack, then you probably have a wiring problem at the jack or leading to the jack for all of the lines. You can open the faceplate and check for loose wires. If it is the wires to the jacks, you may want a professional to deal with the issue.
If you get the in use message at other jacks on both phones, find where the telephone service comes in. If you are lucky, that will terminate in RJ-11 jacks. Then open the service box and use your test phone there. If the problem occurs at the service box, call your phone company. They should fix it for you. If the dial tone is normal, it's an inside wiring problem. The phone company will fix it for a fee. (If the service uses a non-RJ11 jack, you should have the phone company do this test.)
I hope this helps.
(who has gotten a line in use error when mice chew on the wires or a crew dug too deep near the underground wires. Sometimes we'll hear a fast busy signal when the handset is picked up with the problem. Although with 2 line service, only the digging humans usually cause a problem with both lines. Animals only damage on line at a time outside.)
on Apr 18, 2011