A leak or failure of the heat exchanger located under the dashboard can allow hot coolant to escape and cause injury to the feet of a passenger. Hot coolant can also steam up the interior of the vehicle temporarily impairing the driver's visibility, increasing the potential for a vehicle accident.
In the event of a cooling system component failure while the vehicle is driven, the coolant can overheat causing the cooling system pressure to rise to a level where a leak in the heat exchanger can occur.
Dealers will install a bypass valve kit which is designed to route excessively hot coolant to the engine without flowing through the heat exchanger. Dealers will also install a plastic cover underneath the dashboard on the passenger side to ensure that the passenger is not exposed to hot coolant in the event of a leak.