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Home >> Toyota >> 2009 >> Yaris Base, 4D Hatchback >> Repair and Diagnosis >> External Pages >> Different car >> Section 22 (Engine Control System) >> SFI System >> DTC P1121 Coolant Flow Control Valve Position Sensor Circuit Stuck >> Description
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DTC P1121 Coolant Flow Control Valve Position Sensor Circuit Stuck: Description

WARNING: This page is about a different car, the 2009 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.

Refer to DTC P1120  .

DTC TROUBLE DETECTION CONDITION CHART

DTC No. DTC Detection Condition Trouble Area
P1121
  • Water valve position sensor output voltage:

    No change despite the ECM sending a valve control signal or slow response

  • CHS tank outlet temperature sensor output:

    60°C (140°F) or more (when hot coolant recovering starts)

  • CHS tank outlet temperature sensor output:

    No change although the hot coolant is recovered

  • Water valve
  • Cooling system (clogging)
  • ECM