Common Toyota Hybrid DTCs and Their Causes
P0A80 – Replace Hybrid Battery Pack
Meaning:
The hybrid battery pack is deteriorating, typically due to aging or damaged battery cells. Risk of engine shut off while driving in some Lexus models!!!
Possible Causes:
Failing level of voltage difference due to battery imbalance caused by weak battery modules.
P0A7F – Hybrid Battery Pack Deterioration
Meaning:
Hybrid battery pack deterioration is detected.
Possible Causes:
Battery aging, faulty charging circuit, or worn-out cells.
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P0AA6 – Hybrid Battery Voltage System Isolation Fault
Meaning:
This code signifies a problem with the high-voltage system where electricity is detected on the vehicle's frame when it shouldn't be. . Risk of engine shut off while driving!!!
Possible Causes:
Damaged high-voltage cables, faulty battery modules, issues with the battery control module, or a compromised isolation component.
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P0A94 – DC-DC Converter Performance
Meaning:
The DC-DC converter is malfunctioning. Risk of engine shut off while driving!!!
Possible Causes:
Overheating, electrical failure, or faulty components within the converter.
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P0A93 – Inverter Coolant Pump Performance
Meaning:
Inverter coolant pump performance is faulty. Risk of engine shut off while driving!!!
Possible Causes:
Failed pump, clogged cooling system, or low coolant levels.
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Cooling Performance of the Hybrid Battery is Low(Message on dash)
Meaning:
Hybrid battery pack cooling system is not functioning correctly.
Possible Causes:
Clogged cooling fan, low coolant levels, or a faulty cooling fan motor.
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