New 2017 LVL3 GL W/new 2017 Motor Trike Adventure. The TPMS system failure light was not disabled by the dealer. I am an Electronic Mechanic so thought of a way to have the system active for the front tire.
I used 2" PVC pipe with end caps to hold the sensor removed from the takeoff wheel. It holds 45 psi. I wrapped it in bubble pack and put it in the compartment in front of the fuel door. Turned on the bike (not the engine), TPMS failure light was on as expected. I used the VT-15 to initialize the TPMS system which turned off the failure light. Reduced the front tire psi to 30 and the low pressure light came on. Re-inflated to 36 psi and the low pressure light went out. I thought I now had a working TPMS system for the front tire. Went for a ride and after 8-10 miles the failure light came on solid and stayed on. 4 more rides, enabling the system before each ride, but the failure light keeps coming back on. The last time after only 6.5 miles. The system must be looking for something I have not provided.
Additional unrelated info (2nd photo) shows the standard 3V CR2032 battery which Honda welded in place. It can be removed and a new battery soldered in if you have the tools and experience.
The 3rd photo is the Tire Gard External sensor TPMS system I use for all 3 wheels. It gives the actual pressure of each tire. The rear tires in the photo show 44 psi. That photo was taken when I had a Tow Pac kit on a Lvl1 2009. Now It displays 22PSI for the new trike.