My uniden clx485 handset will not power on. I will get the charge light for like 40 seconds, and then no light at all. After I put back on the charger it will light for 2 seconds and then out. I reset the system, I cleaned the contacts with a dry cloth and still the same, it will charge for a little, then nothing. Still no power on. Everything seems to work on the base fine, but I do not know if it is the battery to the handset that is the problem, or the handset itself.

SOURCE: Uniden cordless phones

This sounds like the register-deregister problem elsewhere on this page. Try holding down the "end" and "#" buttons for about 6 seconds to deregister the phones and then reregister them. I had this problem too and it worked for me.

SOURCE: how to deregister a handset without the base with which it orginally registered

I successfully reset uniden TCX800 handset by reconnecting the battery while holding the '*' and '#' key, then press the right upper soft key near LCD.

SOURCE: Out of range

I successfully reset Radio Shack (Uniden) 5561 handset by reconnecting the battery while holding the '*' and '#' key, then press the right upper soft key near the LCD window. The display will indicate "EEPROM/RAM cleared!!" and will return the handset to the factory default condition - looking for a base to register to.

SOURCE: Resetting the Handset

YOU might need to deregister the hand set first by holding down the red end (hang up key) and keep it down while holding the # key. If deregister wont work use base unavailable and yes, you are sure twice.

List the handset numbers of those working handsets
Using a WORKING handset follow these directions
Resetting Handsets
If you want to register the handset to a different base or
replace a handset with another one, you must first clear the
registration information from the base and the handset.
1. Press and hold [ ] and [#] for
at least 5 seconds, until the
SYSTEM RESET menu
appears.
2. Select the DEREGISTER HS
submenu. WHICH HANDSET?
appears in the display.
3. Move the cursor to select the handset ID to be de-registered
from the list, and then press the OK soft key. DEREGISTER HS
appears. CHOSE A NUMBER THAT IS NOT ONE OF YOUR WORKING HANDSETS
4. Move the cursor to select YES, and then press the OK soft key.
When ARE YOU SURE? appears, select YES. You will hear a
confirmation tone.
PUT THE HANDSET IN THE BASE CHARGER AND IT SHOULD REGISTER

Hope This Helps - It worked for me

SOURCE: Register additional handsets on a Uniden phone

From: Uniden Customer Support

On most models you can find an option in the menu for De-register? In that case you would select that option and select to deregister the handset.
TRU88 models you go to the main menu and go to De-register HS select yes to deregister the Handset.

DCT5 and DCT6 models: Press menu on the handset. Go to System Reset and Press select. Go to Deregister HS and press select. Arrow up to yes and press select. Then go back into the menu. Go to system reset and press select. Arrow down to Replacing the base and press select. Arrow up to yes and press select.

DCT7 models: Press and hold "end" and "#" until the system reset menu appears on the display. Then follow the instructions from above for the DCT5 and DCT6 deregister procedures once your into the menu.

TRU4 and TRU5 models: Press and hold xfer/del and end until "de-register?" appears. Use the plus+ button to go up to yes and press select.

To register any of the following phones please see you owners manual under either:


•Register handset or


•Register the digital security code.