High-Voltage Controller 12V Supply Fault
The TESLA-HVP_W024 (Tesla High-Voltage Controller (HVP)) EV fault code means: High-Voltage Controller 12V Supply Fault. This is a serious severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- expert
- Estimated cost
- Often resolved by a 12V low-voltage battery replacement (~$85-$300+); a controller power-feed fault is diagnosed and quoted by Tesla service.
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Common Symptoms
- Service alert related to the high-voltage control system
- May appear together with 12V low-voltage battery warnings
- Possible reduced functionality depending on the underlying condition
- Usually no change in driving unless 12V support is actually lost
Probable Causes (Ranked by Likelihood)
- The high-voltage controller detected a fault in its 12V (low-voltage) supply, often tied to a weak or failing 12V battery Likely
- Wiring, connector, or power-feed problem to the high-voltage controller Possible
Frequently Asked Questions
What does HVP_w024 mean?
The high-voltage controller has detected a fault in its 12V low-voltage supply. The 12V system powers the controller, so the usual root cause is a weak or failing 12V battery or its wiring rather than the high-voltage pack itself.
Is HVP_w024 serious?
Have it checked promptly. It often traces back to a failing 12V battery, which can leave the car unable to start. Start with the 12V battery and its connections.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
Because the 12V system powers the high-voltage controller, start by checking the health of the 12V low-voltage battery and its connections.
Look for companion VCFRONT 12V alerts -- resolving a degraded 12V battery often clears this code.
If the 12V system checks out, the controller power feed needs Tesla service diagnosis (high-voltage area -- not DIY).
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- Tesla firmware alert reference (core-hacked/tesla-alerts-dictionary): HVP_w024_Supply12vFaultcommunity-maintained dictionary, not an official manufacturer document
- Tessie Tesla alert statisticsthird-party Tesla alert reference with owner-telemetry frequency — not an official Tesla document
Commonly Affected Vehicles
- Tesla Model 3
- Tesla Model Y
- Tesla Model S
- Tesla Model X
- Tesla Cybertruck
Related Codes
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