P0A94 Possible Causes
- Faulty inverter with converter assembly
- Inverter with converter assembly harness open or shorted
- Inverter with converter assembly circuit poor electrical connection
What Does It Mean?
How to Fix Code P0A94
Check 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 pins.
P0A94 Possible Symptoms
Malfunction indicator lamp illuminated (or service engine soon warning light)
P0A94 Meaning
The boost converter contains an IPM (Intelligent Power Module), which includes an IGBT (Insulated Gate Bipolar Transistor) and a reactor. The HV control ECU operates the IGBT, which controls the current in the reactor.
The boost converter increases the high voltage DC rated at 201.6 V to an approximate DC voltage of 500 V. The inverter converts the voltage that has been increased by the boost converter to alternating current, which is used to drive the MG1/MG2. When the MG1/MG2 operates as a generator, the approximately 500 V alternating current from the MG1/MG2 is converted to direct current by the inverter.
Then, the boost converter drops this voltage to a DC voltage rated at 201.6 V in order to charge the HV battery.
The HV control ECU uses a voltage sensor built into the boost converter to detect the high voltage (VL) before it is amplified. Additionally, it uses a voltage sensor built into the inverter to detect the high voltage (VH) after it is increased.
Based on the voltage before and after its increase, the HV control ECU boosts it to a target voltage by controlling the operation of the boost converter.