Start with the records. Repair orders, warranty documents, mileage, and days out of service are more useful than general assumptions about whether a vehicle qualifies.
When an electric or hybrid vehicle throws a “High Voltage System Error,” refuses to start, or suddenly loses power, the culprit can be a failing HV (high-voltage) system contactor. This small but critical component controls the flow of high-voltage energy from the traction battery to the vehicle. If your dealer has tried and failed to fix an HV contactor issue multiple times, or your EV has spent weeks in the shop, California’s lemon law may provide important protections. The overview below explains the basics in plain language and offers practical steps to document what’s happening—so you can discuss options with a professional.
EV HV Contactor Failures: What California Law Says
The HV contactor is essentially a heavy-duty electric switch that “closes” to allow the battery pack to power your EV or hybrid. When a contactor sticks, welds, or fails to close, common symptoms include no-start conditions, sudden shutdowns, “Service High Voltage System” warnings, inability to charge, clicking sounds on startup, or intermittent power loss. These problems can be sporadic, which is frustrating for owners and challenging for technicians to reproduce. Still, they are typically covered under the manufacturer’s new vehicle warranty and can constitute a substantial impairment when they affect drivability, safety, or charging.
Under California’s Song-Beverly Consumer Warranty Act (often called the California Lemon Law), manufacturers must repair warranty-covered defects within a reasonable number of attempts. There’s a legal “presumption” that may apply if the issue occurs within the first 18 months or 18,000 miles, whichever comes first, but your rights can extend throughout the warranty period even if the presumption doesn’t apply. Generally, multiple unsuccessful repair attempts for the same problem—or 30 or more total days out of service for repairs—can support a claim. Safety-related defects, such as sudden loss of propulsion, may require fewer attempts. Each situation is fact-specific, and the details of your repairs and timing matter.
If your EV’s HV contactor failure persists despite dealer repairs, potential remedies under the law can include a repurchase (buyback) or replacement, as well as reimbursement for certain incidental expenses like towing or rental vehicles. In some cases, federal law (the Magnuson-Moss Warranty Act) may also provide protections for warranty disputes. Every case is unique, and outcomes depend on the vehicle’s history, the number and type of repair attempts, and the manufacturer’s response. This is general information—not legal advice—and you’ll want to consult a lawyer to evaluate your circumstances.
Tips to Document Repairs Under California Law
Start by building a clean paper trail. Each time you visit the dealer, describe the symptoms in your own words and ask that they be written exactly on the Repair Order (RO). Request a copy of every RO and invoice—even if the dealer says “No trouble found,” “Unable to verify,” or performs a software update at no charge. Note the date, mileage, and how the issue affected your ability to drive, charge, or use the vehicle safely. Consistent, detailed service records help show repeated issues with the same component over time.
EV-specific details are especially helpful. Take photos or short videos of dashboard warnings, start-up error messages, and any “Service HV System” alerts. Keep a simple log of when the car fails to start, when charging stops unexpectedly, the state of charge (SOC), outside temperature, and where you were charging (home Level 2, DC fast charger, etc.). Save tow receipts, loaner agreements, and any texts or emails with the dealer or manufacturer. If the dealer performs software flashes or HV system calibrations, ask that version numbers and technical service bulletin (TSB) or campaign IDs be listed on the RO.
Be proactive and precise with the service department. At drop-off, ask the advisor to road test under the same conditions that trigger the fault (for example, after an overnight cold soak or immediately following a DC fast charge). Request that diagnostic trouble codes (DTCs), cause, and correction be documented. If the issue repeats, schedule the next appointment promptly and reference prior ROs by date. You can also ask the manufacturer for a case number if the problem persists. Accurate documentation doesn’t guarantee any outcome, but it gives you a clearer picture of your vehicle’s history and helps a professional assess your options.
ZapLemon helps California drivers understand their rights when EV or hybrid HV contactor failures won’t go away. This article is for informational purposes only, is not legal advice, and reading it does not create an attorney-client relationship. Results depend on many factors, and no law firm can guarantee outcomes. Attorney Advertising.
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