P0A94 on Tesla
DC/DC Converter Performance
P0A94 on Tesla vehicles indicates dc/dc converter performance. Au7o has documented this code across 1 Tesla model — most commonly on Model S. This hybrid/electric vehicle code sets when the hybrid control system detects that the DC/DC converter is not performing within expected parameters. The DC/DC converter steps the high-voltage battery power down to the 12-volt level that runs the car's lights, accessories, and control modules, so a performance fault can affect the whole low-voltage system. Symptoms may include warning lights, reduced power, the hybrid system not starting, or a discharged 12-volt battery. Because high-voltage components are involved, diagnosis and repair should be done by a qualified hybrid technician. Typical repair costs on Tesla range from $220 to $1,800, depending on the specific model and root cause.
Common Causes of P0A94
- •Faulty inverter/converter assembly (DC/DC converter)
- •Open or shorted wiring in the converter circuit
- •Poor electrical connection at the converter
- •Weak or failing 12-volt battery
- •High-voltage system or cooling fault affecting the converter
- •Software/control module calibration issue
- •Faulty hybrid control module (less common)
P0A94 on Tesla by Model
Tesla Model S(1 issue)
- 12V Auxiliary Battery / DC-DC Converter Failure Cascade2012-2021
The low-voltage 12V lead-acid battery on early-to-mid Model S (concentrated in 2015-2018 build years) fails prematurely due to a poor original vendor cell plus constant vampire-load strain from always-on electronics. Roughly a third of Tesla NHTSA low-voltage complaints trace here. A weak 12V triggers a cascade of seemingly unrelated warnings, screen glitches, lock/unlock weirdness and 'car won't wake up.' In a subset of cars the real culprit is a failing DC-DC converter that stops properly charging the 12V, which owners misdiagnose as just a dead battery. A dead 12V can leave the car completely immobilized/locked.
Looking for P0A94 on a different make?
View P0A94 across all makes →Frequently Asked Questions
What does P0A94 mean on Tesla?▼
P0A94 stands for "DC/DC Converter Performance." This hybrid/electric vehicle code sets when the hybrid control system detects that the DC/DC converter is not performing within expected parameters. The DC/DC converter steps the high-voltage battery power down to the 12-volt level that runs the car's lights, accessories, and control modules, so a performance fault can affect the whole low-voltage system. Symptoms may include warning lights, reduced power, the hybrid system not starting, or a discharged 12-volt battery. Because high-voltage components are involved, diagnosis and repair should be done by a qualified hybrid technician. On Tesla specifically, this code is documented across 1 model.
What causes P0A94 on Tesla vehicles?▼
Common causes on Tesla: Faulty inverter/converter assembly (DC/DC converter), Open or shorted wiring in the converter circuit, Poor electrical connection at the converter, Weak or failing 12-volt battery, High-voltage system or cooling fault affecting the converter. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0A94 on a Tesla?▼
Repair costs on Tesla range from $220 to $1,800, depending on the specific model and root cause.
Which Tesla models have P0A94 documented?▼
Au7o has documented P0A94 on 1 Tesla model: Model S.