Toyota 2006 Highlander Owner's Manual page 169

Message
Transmission is out of the "P" position
(m)
when starting the hybrid system.
(n) Fuel door is left open.
'06 HIGHLANDER HB_U (L/O 0503)
Status
Shift the transmission to the "P" position when starting
the hybrid system.
Close the fuel door.
2006 HIGHLANDER (Hybrid) from Mar. '05 Prod. (OM48530U)
Action
157