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Home >> Toyota >> 2007 >> Prius Base >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> SFI System >> DTC U0293 Lost Communication with HV ECU >> Monitor Description
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Monitor Description

The ECM and the HV control ECU are connected through a set of communication lines on the CAN, in order to maintain mutual communication. The ECM uses the communication lines to transmit the engine speed or other pieces of information to the HV control ECU. The HV control ECU transmits signals such as an engine torque request signal to the ECM.

A few seconds after the power switch is turned ON (IG), the ECM starts checking for any malfunction in the communication with the HV ECU. If the ECM detects a malfunction in the communication, the ECM sets a DTC and illuminates the MIL.