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Home >> Toyota >> 2014 >> Prius Plug-in >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 34 (Engine Control System (Diagnostic Codes & Circuit Tests) (Except Plug-In)) >> SFI System >> DTC P261B: Engine Coolant Pump "B" Control Malfunction; DTC P261C: Engine Coolant Pump "B" Control Circuit Low; DTC P261D: Engine Coolant Pump "B" Control Circuit High [10/2013 - ] >> Monitor Description
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Monitor Description

WARNING: This page is about a different variant/trim than selected.

The ECM calculates the speed of the engine water pump assembly using a duty cycle signal sent from the engine water pump assembly. When the speed of the engine water pump assembly becomes less than 900 rpm while it is operating, the ECM detects the malfunction and stores DTC P261B.

The engine water pump assembly operates steplessly based on a duty cycle signal sent from the ECM. If actual drive duty cycle does not correspond to the target drive duty cycle of the engine water pump assembly, the ECM detects the malfunction and stores DTC P261C or P261D.