This bulletin applies to all Honda Odyssey models with one-push start buttons.
When you shift into park and shut off the engine, does the power mode stay in "on" or "accessory?" The culprit could be a misadjusted shift cable. If it is not adjusted right, it puts pressure on the shift lever, keeping the park pin switch from opening. The power control unit needs the park pin switch position input to switch the power mode to "vehicle off (lock).
To find and fix this problem, hook up the HDS, and go to the one-push start/PCU data list. Scroll down to at shift position P and at shift position P-Pin.
Shift into park while keeping your foot on the brake pedal. Then, without pressing the release button, pull back on the shift lever (toward reverse). The at shift position P signal should read "on" and the at shift position P-Pin signal should read "off."
If you don’t get the expected results from either of those tests, refer to the electronic service manual and adjust the shift cable.