T289 battery replacement. Does the clip have to come off the back before sliding down the U shaped black bottom?

I had the same problem - here was my fix...

If you remove the warming drawer you will see the heating coil underneath the drawer held in place by three c-shaped clips that are screwed to the bottom of the stove. I finally realized the two front clips (open to the front of the drawer opening) had their tops pushed vertical and that was what was blocking the drawer from going back in. I bent and hammered the clips back into shape and also hammered the bottom of the drawer back into shape where I had bent it on the clips. Then was all good following the manual instructions.

From the scratches on the drawer bottom, it looks like the clips were installed that way at the factory. This was the first time I's had the warming drawer all the way open.

The battery compartment is revealed by pulling down on the two U shaped sides of the radio. This U shaped black part along with the lower portion of the back of the radio will slide down and off the radio to reveal the batteries.

The black u-shaped bottom is attached to the back of the radio. It is all one piece. Grasp and pull down on the u-shaped portion and it will slide down and off the radio exposing the battery compartment.

Best regards.

The Partner ACS system uses 2 AAA batteries to retain programming from 45 to180 days, in the event of a power outage. When these batteries fail, a system warning (replace sys bat w/ power on) will display on the screen of extensions 10 and 11.With new batteries in hand, go to the phone system cabinet and find the system processor. The system processor will be marked on the top third of the card with a label marked "Partner ACS processor".
On the bottom of the processor module,below the extension jacks, there is a battery compartment. With the power on, Push in slightly on the battery compartment and slide the black locking latch up to cover the"+" icon. Remove the battery assembly by pulling the tab at the bottom of the compartment cover.Place the batteries into the metal battery clips fully. Make sure the polarity of the batteries is correct by looking inside the metal battery clips for the "+" and "-" icons cut into the metal of the battery clip. With the locking latch in the unlocked (up) position slide the battery assembly back into the processor card far enough that the edges of the assembly slip behind the plastic housing of the processor card.Slide the locking latch down to secure the battery compartment. The message on your screen will disappear if the batteries are inserted correctly.

The black U-shaped part will slide down and off the radio. It is one piece including the sides, bottom and part of the back of the radio.

Best regards.

The black U-shaped sides, which are attached to the back, slide down and off the radio as one piece.

I got one at a garage sale for a buck. Came here for a solution, but still couldn't get it open. I figured it out by breaking it!. Bad for me, good for you. I pried off the black cover and broke off a little tab. I'll explain how it works. Behind the two buttons there is a silver half oval. When you push down on the end of that half oval that's the farthest away from the mouse wheel, it pushes down on a little tab that is part of the black cover, and lets that tab clear a piece of plastic that it clips under. I broke off that tab by prying it. So, push down hard on the END of that little half oval and at the same time slide the black cover back. The mouse uses two AAA batteries. Good luck. That's the solution. Guaranteed!

The black "U" shaped bottom slides down and off the main radio.

The black "U" shaped bottom slides down and off the radio.