When the battery on your AMB transponder withers or dies, place it on your trusty workbench and give this hack a whirl. What do you have to lose? Besides your AMB warranty of-course?
My transponder laid dormant for a couple of years and completely died in storage. I had the earlier model TranxX 260 with the 4 screws (seen below). The later ones appear to be completely sealed which may need a little more labor.
Here's a video of a guy cutting out the battery from a sealed unit:
Another option is sending your unit to Australia for a more professional repair:
The last and least expensive option is making the repair yourself. Below are the steps I took to repair my transponder which is still working fine after a year.
STEP 1: Remove the 4 screws
STEP 2: Liberate the old battery.
Notes: Use a heat guy and take your time. I placed foil over the sections I was not removing and used several small picks and a box cutter to expose the battery and connectors. Once the epoxy was free I broke the weld from the battery posts and removed the battery.
STEP 3: Install and secure new battery.
Notes: I purchased a 1.2V 2700 mAh battery from the local battery store (Batteries Plus) for $3 and asked them to weld/arc the tabs on for me. A couple of dabs of solder to the existing leads is enough to hold. I mounted the battery with craft glue.
STEP 4: Re-install screws, charge and spend that $400 you just saved on that new set of cams you've been wanting. See you in the paddock!