TSB: REVISION NOTICE November 21, 2018 Rev1: ? The Required Tools & Equipment section has been updated. Any previous printed versions of this bulletin should be discarded. Some 2010 model year Prius and Prius Plug-in Hybrid vehicles may exhibit a condition where the brake, ABS, and/or TRAC warning light(s) are on and/or a Check VSC message displays. Diagnostic Trouble Codes (DTCs) C1252, C1253, C1256, and C1391 may be stored. This condition may be caused by a small internal brake fluid leak inside the brake booster assembly with master cylinder. Follow the Repair Procedure in this bulletin to address this condition.
