OBD-II · Engine and powertrain (P)
P0A94
DC/DC converter performance
What it means
A DC/DC converter is not performing as commanded. Identify the converter from the vehicle and subcode: on many Toyota/Lexus hybrids this is the high-voltage boost converter in the inverter assembly, not the converter charging the 12V battery.
Symptoms
- Hybrid/EV warning light
- Reduced power or loss of drive
- Vehicle may not enter READY
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | internal boost-converter or inverter power-module fault |
| 02 | converter overheating or a cooling-system fault |
| 03 | converter control, feedback wiring or voltage-sensing fault |
| 04 | related motor, generator or control-unit fault identified by the subcode |
What to check, step by step
- 01Save all hybrid codes, information subcodes and freeze-frame data; identify the converter in the OEM diagnostic procedure
- 02Check relevant service campaigns and software bulletins
- 03Check the specified cooling system, with coolant level inspected cold
- 04Have a high-voltage qualified technician follow the subcode-specific control, sensing and converter tests
- 05Do not use normal 12V charging voltage to rule out a high-voltage boost-converter fault