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P0AA4 Severity
Identifying an OBD code is just the start of a complete diagnostic routine. Most trouble codes are caused by a sensor reporting a value that is out of range. Just replacing a sensor may not fix underlying issues. Be sure to understand the code, the part or system in your car that the code refers to, and the risks of delaying professional repair.
Proper diagnosis will save you time and money on unnecessary repairs.
Urgent codes indicate immediate action is necessary. These are urgent and significant malfunctions that can cause severe damage to the vehicle or harm the driver and passengers.
The High Voltage System is engaged and disengaged through the Hybrid Control Module. If the Hybrid Control Module cannot control the circuit to the high voltage battery, code P0AA4 will set.The Hybrid Control Module may disable the high voltage system.
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OBD-II Code High voltage system may not operate is defined as a Hybrid Battery Negative Contactor Circuit Stuck Closed
The High Voltage System is engaged and disengaged through the Hybrid Control Module. If the Hybrid Control Module cannot control the circuit to the high voltage battery, code P0AA4 will set.The Hybrid Control Module may disable the high voltage system.