Hi, my name is Jose Sebastian, your mechanic automotive expert, and I will be happy to assist you today. In some cases, I may need more information to assist better. I apologize for any delay.
I try to be here most weekdays and some weekends. If you respond and I do not respond back right away I will do so as soon as I can.
Dear customer, you are presenting a clear deprogramming problem in the alarm system. The problem is that I do not know if it happened due to the installation of the electric seat or due the flat battery.
When a battery is flat it is normal that certain electronic modules are deprogrammed in this case the alarm module, but solving this is not complicated but it does require a diagnostic tool with Honda software to be able to access the electronic modules including the alarm and to be able to do a factory data reset in this way the vehicle would be working with the original data, in this case the alarm module would be working normally.
This in the case that it has been deprogrammed due to a battery discharge, the problem is that if when installing the seat one of the circuits in alarm was touched, it could have caused a problem in the wiring of said module or a defect in it. Would be good to verify how you made this installation to verify that there has not been a short or high voltage that the module could find, if it is possible to get a test module to rule out.