IIRC, TSB 15-072 updates the audio unit software to fix an issue with the headunit hanging and sometimes failing to turn off ( draining the battery). "Campaigns" 13-001 and 13-024 change the firmware in various embedded modules throughout the car, not just the audio unit firmware. TSB 16-008 updates the engine and transmission controllers to mitigate surging and other transmission issues, and TSB 16-025 addresses audio "fading in and out" when listening to FM radio. Does this update the tuner module firmware or the headunit ? There is another TSB to replace tuner modules.Here are the updates the dealer did to my audio unit on my Elite: 13-001, 13-024, 15-072
They all get installed via the USB connection to the audio unit. Every once in a while someone asks if they can just rip out their headunit and install an aftermarket unit, and this is one very good reason not to do that.
My understanding is that the updates are delivered to dealers on USB sticks, or the dealers can download them from Honda and put them on their own USB sticks. Some of the "updates on USB sticks" seem to be listed as service parts that can be purchased by anyone, just to make things even more confusing. But the transmission update requires that the tech verify firmware revision levels of modules, ( MVCI and HDS, whatever those are ) prior to installation and "clear any codes" generated during installation. I don't think anyone can do that without a Honda scan-tool. The trans update also requires "idle-learn" procedure afterwards, and failure to do that according to spec can cause problems. This is what happens when vehicles turn into rolling mainframe computers. Patch after patch after patch.