2010Tacoma TPMS rebuild

After 15 years my 2010 Tacoma Tire Pressure Monitor System batteries began to fail.
Instead of paying $400 for replacements including the TPMS code reader I decided to buy a Hakka soldering station and 4/3 volt battery replacements.
The original sensors have a plastic cover that is easily pried off with a screwdriver once the sensor is removed from the rim/tire.
Under the plastic cover is potting compound that encases the battery and radio frequency electronics and pressure monitor.
That soft potting compound must be excavated from the battery and electronics. I used a blunt plastic probe to gently erode the compound into tiny clumps. There are 2plastic clips holding the battery and the electronics is pinned on two plastic locating posts.
Once most of the compound is removed gently insert the plastic probe under the battery and lift it while spreading the clips holding it. It is soldered to the electronics circuit board so the board must also gently be lifted off the locating posts with that plastic pointer. Be very gentle as the are tubing on that Circuit board.
Once released from the case the remaining potting compound can be totally removed using the probe from around the two solder points on the circuit board holding the battery to the electronics. Use your DVM meter set on voltage to determine the correct Plus and minus polarity of the battery to the circuit board.
Use flux coated wicking copper braid to desolder the plus/minus connection of the battery. YouTube tutorials show how easy this is.
You can buy  the special high dollar F welded connectors that are welded to the new 3volt battery replacement but I used the copper braid to connect the new batteries to the circuit board. Just make sure the polarity is correct
Once the new battery is soldered in place and replaced in the sensor housing buy some 2 part liquid potting compound  and entomb it back into the housing  The compound takes 24 hours to cure. Silicone caulk is acidic and should not be used