Fuel Pump Control
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2017 Honda Odyssey, 2016 Honda Odyssey, 2015 Honda Odyssey, 2014 Honda Odyssey, and 2013 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.
When the ignition switch is turned to ON (II), the PCM grounds PGM-FI main relay 2 which feeds current to the fuel pump for 2 seconds to pressurize the fuel system. When the engine starts, the PCM grounds PGM-FI main relay 2 and feeds current to the fuel pump. When the engine is not running and the ignition switch is in ON (II), the PCM cuts ground to PGM-FI main relay 2 which cuts current to the fuel pump.