Check Engine Light Due to Failed Three Way Coolant Control Valve: Toyota Prius Engine & Powertrain

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 comments

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Toyota Prius vehicles with this problem

8 model years affected

Average mileage: 107,639 miles

(15,000 - 230,000)

Repairs related to this problem

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Check Engine Light Due to Failed Three Way Coolant Control Valve on Toyota Prius

Problem overview

Toyota Prius vehicles with this problem

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