Check Engine Light Due to Failed Three Way Coolant Control Valve on Toyota Prius
Problem overview
The Check Engine Light may illuminate with a fault code P1121 stored. It is commonly caused by a failed three way coolant control valve. Valve replacement is recommended if this occurs.
257 people reported this problem
109 commentsToyota Prius vehicles with this problem
Average mileage: 107,639 miles
(15,000 - 230,000)
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