Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
Toyota recently released a warranty enhancement for 2010-2014 Prius, extending the coverage of the inverter/converter Intelligent Powertrain Module.
Toyota Bulletin Information:
Toyota has received some reports where the Intelligent Power Module (IPM) located inside the inverter assembly of the hybrid system may fail. This condition is indicated by hybrid system diagnostic trouble codes (DTCs): P0A94, P324E, P3004, and/or P0A1A. If one or more of these DTCs are detected, various warning lamps on the instrument panel will also illuminate and the vehicle will enter fail safe mode.
Although the Hybrid Inverter assembly is covered by Toyota’s New Vehicle Limited Warranty for 8 years or 100,000 miles (whichever occurs first), we at Toyota care about the customers’ ownership experience. Toyota is now extending the warranty coverage for repairs related to failure of the Intelligent Power Module (IPM).
The cost to diagnose the P0A94 TOYOTA code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
The boost converter contains a booster IPM (Intelligent Power Module), which includes an IGBT (Insulated Gate Bipolar Transistor) and a reactor. The HV control ECU actuates the IGBT, which controls the current in the reactor.
The boost converter boosts the high-voltage direct current rated at 201.6 V to an approximate direct current voltage of 500 V. The inverter converts the voltage that has been boosted by the boost converter into alternating current, which is used for driving the MG1/MG2. When the MG1/MG2 operates as a generator, the alternating current of approximately 500 V from the MG1/MG2 is converted into direct current by the inverter.
Then, the boost converter drops this voltage to a direct current voltage rated at 201.6 V in order to charge the HV battery.
The HV control ECU uses a voltage sensor that is built into the boost converter to detect the high voltage (VL) before it is boosted. Also, it uses a voltage sensor that is built into the inverter to detect the high voltage (VH) after it has been boosted.
Based on the voltage before and after it has been boosted, the HV control ECU boosts it to a target voltage by controlling the operation of the boost converter.
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