Toyota Code P0A90 Hybird vehicals Fault Trouble
When this trouble code appears in your Hybird car that means your car refuse to go on EV mode.Toyota has received some reports where the Intelligent Power Module (IPM) located inside the inverter assembly of the hybrid system may fail.

What causes this problem with the DC/DC Converter Performance?
There can be inoperative inverter with converter assembly
There can be opened or shorted inverter with converter assembly harness
Inverter with converter assembly circuit inferior electrical connection
How To Correct P0A94 DC/DC Converter Performance
If you wish to correct this fault code, then you have to follow certain steps. Correcting a problem needs your careful attention. Here are some ways with the help of which you will be able to correct the OBD Code P0A94:

Make sure to mend the faulty electronic control unit
It is essential to restore the flawed powertrain control module
Repair or replace the quirky converter assembly
Rehabilitate the defaults in the converter assembly circuit
The malfunctioning converter assembly harness should be repaired or replaced as per the need
Carefully adjust the faults in the body control module component
