NHTSA Complaint #11464119 — 2009 LEXUS LS

My wife was driving, we got check engine & VSC sign, we checked with car mechanic, who asked us to take to dealer, they diagnosed & fixed some parts & charged us around 1000.00 $, Next day she drove around 6 miles, she was ready to enter highway sign came, stop car immediately at safe place, she called dealer who advised to bring car back, she took car back ,they diagnosed again & told us it will cost 4042.11 to replace brake actuator & brake pump,we searched that this was manufacturing defect, we contacted Lexus corporate office, they said that it factory defect only till 2018 & declined to fix,they said they send us letter,we never received any letter.Car mileage is around 120,000 only,my wife narrowly escaped accident, Is not dealer responsible to contact customers by phone or E mail for safety issues ,moreover we took car to dealer multiple times for not staring ,they fixed battery all the time , we also got car maintainece service from the dealer many times ,was not it their responsibility to make us aware for this defect & fix? they should have diagnosed this problem when we took car for VSC & engine check sign? Pleas investigate so no body else suffers or dies in an accident, Thanks