The contact owns a 2018 Toyota Prius. The contact stated while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken to the dealer where it was diagnosed with a failed heat exchanger, catalytic converter, and exhaust system. The contact was informed that the heat exchanger, the catalytic converter, and the exhaust system needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 89,682.