Deregister AT&T SL82118 handset

The extra handset for the TL86109 is the TL86009. The manual for this handset is on the accessory handset page: https://telephones.att.com/pd/379/TL86009-Accessory-handset-with-caller-ID-call-waiting ; see the Support & Manauls tab. The direct link to this manual is https://att.vtp-media.com/products/TL/TL86009/TL86009_CIB_i8.0_20170526.pdf .

Make sure that the base has power and is connected to a working phone (land) line. To deregister all handsets, press and hold the Flash (on the left below the volume buttons) on the base for about 4 seconds. You'll see "Deregister all handsets?". Release the Flash button. Press the Yes soft key (below the LCD screen). You should see the base LCD screen read "Please wait". The registered handsets should read "Out of range or no power at base" until the deregistration is complete. Then you should see the message "Press Hold on base for 4 seconds and then press # on the handset" on all the handsets. The instructions are on pages 11/12 (page 15/16 of the PDF) of the handset manual. They are also in the full manual for the TL86109 on pages 135/136 (141/142 of the PDF) available here: https://att.vtp-media.com/products/TL/TL86109/TL86109_CIB_i14.0_20170526.pdf .

I hope this helps.

Cindy Wells

This sounds like Handset #1 has lost its "registration" with
the base. De-registering & re-registering is often easy.

First, be sure the handset battery is well charged as a
weak battery will interfere with the registration process.
Then try this ( 'works for the D1680, D1481, & similar):

To deregister the handset:

1. Press and hold the [END] and [ # ] keys at the same time,
after a few seconds the display will say
"System Reset, Deregister Handset"
press [SELECT]
scroll to "Base Unavailable"
press [SELECT] (chirps) press [END]
display reads "Place in base..."

Next, to re-register the handset:

2. Set the handset into the base cradle and wait,
within ~30 seconds the handset should display
a "Handset #" and be good to go.

Good luck!
--------------

This sounds like the handset has lost its "registration" with
the base. De-registering & re-registering is often easy.

First, be sure the handset battery is well charged as a
weak battery will interfere with the registration process.
Then try this ( 'works for the D1680, D1481, & similar):

To deregister the handset:

1. Press and hold the [END] and [ # ] keys at the same time,
after a few seconds the display will say
"System Reset, Deregister Handset"
press [SELECT]
scroll to "Base Unavailable"
press [SELECT] (chirps) press [END]
display reads "Place in base..."

Next, to re-register the handset:

2. Set the handset into the base cradle and wait,
within ~30 seconds the handset should display
a "Handset #" and be good to go...

Good luck!
--------------

Called the manufactuer.... To do this enter on the handset you want to deregister:

*331734# and press (Menu Key# 1 - top uppermost left button that is unmarked).


This will put the handset back into the register mode.



Hope this helps,

James Pavicic Jr

Getting startedReplace a handsetIf you want to replace a handset or reassign the designated handset numberof a registered handset, you must deregister all the handsets and thenindividually register each handset.To make deregistration easier, read all of the instructions on this page beforeyou begin. To deregister all handsets:Press and hold FIND HANDSET on the telephone base for about 101.seconds (until the IN USE light on the telephone base turns on and starts toflash), then release FIND HANDSET.Press and release FIND HANDSET again. You must press FIND HANDSET2.while the IN USE light is still flashing. The IN USE light flashes forapproximately seven seconds.All system handsets show CONNECTING... The deregistration process3.takes about 10 seconds to complete. All handsets show NOT REGISTEREDwhen the deregistration completes.If deregistration fails, you might need to reset the telephone and try again.To reset:1.Pick up the registered handset and then press talk/flash.Press OFF/CLEAR and place the handset back in the telephone base.2.-OR-1.Unplug the power from the telephone base, then plug it back in.You cannot deregister a handset if any system handset is in use.

you dont need to deregister it if you have not registered all 8 hand sets with your base unit. Just register the new one and the base will assign a new # for this new. I you had registered 8 hand sets with your base already, you need to remove(deregister0 one handset from your base(it can take only upt 8).
If it still not registering please deregister as follows:
on the base unit, press program, them mute, then enter 335#, then enter the handset number you wish to deregister.
after deregistering try to register your new hand set.

If you are not too far away-not "out of range" then try rehoming/pairing the handset with the base unit. You probably need the phones together to do this. Your manual will explain how-it will have been done in the original setup.

The "END" and "#" key combination can be used for several purposes:

1) If wanting to use an ALREADY REGISTERED HANDSET on an alternate base, and if if the INITIAL BASE isn't available to deregister the handset:

1a) Press "END" + "#" until it for 5+ seconds (wait for it to beep)
1b) Choose the "Base Unavailable" option
1c) That'll deregister the CURRENT HANDSET so that it can be re-registered on ANY base.

2) If a BASE has a handset registered to it which you no longer want registered but the registered handset is missing or broken:

2a) Grab another WORKING handset which is properly REGISTERED to the BASE in question
2b) Press and hold the "END" + "#" key for 5+ seconds (wait for it to beep)
2c) Choose the "Deregister HS" menu option
2d) Pick the REGISTERED HANDSET # to de-register. (Every other registered handset EXCEPT THE ONE YOU'RE ON will appear in the list!)

If the handset has previously worked with the base - press the hangup button and the # key at the same time on the handset for five seconds and follow the prompts to deregister the handset. (System reset - deregister HS - which handset) It will tell you that the handset is deregistered. Then put the handset onto the base and it will register the handset.

I have a Panasonic KX-TG6700 base unit and KX-TGA670B handsets. We had a similar problem where we were no longer able to deregister the handset using the handset itself. We wanted to be able to use that slot that the broken phone was still occupyng. The solution that we found in the manual online was to hold down the intercom button for 3 seconds until the "in use" light turned on. Then press and hold the number of the extension you want to deregister until it beeps. At this point the base unit has freed that extension.