Toyota 2013 Prius Owner's Manual page 570

Stop the vehicle immediately.
A buzzer sounds and a warning message is shown on the multi-infor-
mation display. The following warnings indicate the possibility of dam-
age to the vehicle that may lead to an accident. Immediately stop the
vehicle in a safe place and contact your Toyota dealer.
Warning message
(U.S.A.)
(Canada)
PRIUS PHV_OM_OM47787U_(U)
5-2. Steps to take in an emergency
Indicates an abnormal engine oil pressure.
The warning light may turn on if the engine oil pres-
sure is too low.
Indicates a malfunction in the hybrid system.
Details
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