Since an official English version from Honda Japan doesn't exist, several specialist companies provide professional English translations of the original Japanese handbook: JDM Manuals : Offers a translated English manual for the Honda Shuttle Hybrid (2015–2022)
The manual states this often occurs after refueling if the gas cap is loose. Tighten until three clicks. If the light stays on, the purge valve may be stuck. Do not drive more than 50 miles; visit a mechanic to clear the code (P0456). honda shuttle hybrid user manual english