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Home >> Lexus >> 2020 >> UX 200 Luxury >> Repair and Diagnosis >> External Pages >> Different car >> Section 42 (Hybrid Control System (Diagnostic Codes) (2 Of 5)) >> Hybrid Control System >> DTC P0AA0-00: Hybrid/EV Battery Positive Contactor Circuit Stuck Closed [10/2018 - ] >> DTC Summary

DTC Summary

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  1. MALFUNCTION DESCRIPTION 

    The hybrid vehicle control ECU detects a stuck closed malfunction of a system main relay on the HV battery positive (+) terminal side.

    The cause of this malfunction may be one of the following:

    Inverter voltage sensor (VH) internal circuit malfunction 

    • Voltage sensor (VH) malfunction
    • Motor generator control ECU (MG ECU) malfunction
    • Communication (wire harness) malfunction

    High voltage system malfunction 

    • HV battery junction block assembly malfunction

    Low-voltage circuit (12 V) malfunction 

    • Hybrid vehicle control ECU malfunction
    • HV battery junction block assembly malfunction
    • Low voltage wire harness malfunction
    • Low voltage connector malfunction