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
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).
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.
Sources
This page is built from documented references. Verify against your own service info before repair work.