If your car’s driver-assistance features have started acting up—think sudden phantom braking, a constant “radar blocked” warning, or adaptive cruise control that won’t engage—you may be dealing with a radar sensor calibration problem. These issues often follow windshield or bumper repairs, minor collisions, or even software updates, and they can be frustrating and unsafe. Below, ZapLemon explains how California’s lemon law can apply to radar sensor calibration defects, what to document, and when it might be time to speak with a California lemon law firm. This article is for general information only and isn’t legal advice.
California Lemon Law for Radar Sensor Calibration Issues
Modern vehicles rely on radar sensors and related ADAS (Advanced Driver-Assistance Systems) for features like adaptive cruise control, automatic emergency braking, blind-spot monitoring, and cross-traffic alerts. These systems require precise calibration to work correctly. If the calibration is off—whether from a windshield replacement, bumper repair, alignment work, or a component failure—you might see warning lights, experience false alerts, or notice the vehicle braking or steering unexpectedly. Persistent calibration faults can be more than an annoyance; they may compromise safety and affect the vehicle’s usability and value.
California’s Song-Beverly Consumer Warranty Act (often called the California Lemon Law) generally requires manufacturers to repair warranty-covered defects within a reasonable number of attempts. If they can’t, the manufacturer may be obligated to repurchase or replace the vehicle. The law can apply to new and, in many cases, used or certified pre-owned vehicles that are still under the manufacturer’s warranty and purchased or leased in California. There is also a “lemon law presumption” for certain issues within the first 18 months or 18,000 miles, including a threshold for cumulative days out of service, but whether that presumption applies depends on specific facts.
Radar sensor calibration problems can fit within this framework when they persist despite repeated repair attempts or keep your car at the dealer for extended periods. For instance, if your vehicle repeatedly fails static or dynamic calibration, throws recurring fault codes, or triggers ongoing false braking even after software updates and sensor replacements, that may suggest a nonconformity under warranty. Safety-related malfunctions—like unreliable collision avoidance—can weigh heavily, but every situation is fact-specific. A consultation is the best way to evaluate how California’s lemon law may apply to your circumstances.
What to Document and When to Contact ZapLemon
Good documentation is essential. Save every repair order and invoice, especially those noting “calibration,” “radar alignment,” or “ADAS aiming,” and keep track of dates, mileage in and out, and total days your car is out of service. Ask the service department for calibration printouts, alignment specs, diagnostic codes, software version numbers, and any references to technical service bulletins (TSBs) or recalls. If safe, record short videos of warnings, phantom braking, or messages like “front radar unavailable” to help demonstrate the issue.
Keep your warranty booklet and note any extended warranties or service contracts. If you’ve replaced the windshield or bumper, write down the date, the shop’s name, and the glass or parts used. Save communications with the dealer or manufacturer, including emails, texts, and case numbers. If the dealer says the vehicle is “operating as designed” yet the problem continues, ask them to explain their testing and calibration process in writing. Avoid modifying sensors or installing accessories near the radar or camera areas, as this can complicate diagnosis and coverage.
Consider contacting ZapLemon when you’ve had multiple unsuccessful calibration attempts, the vehicle experiences safety-related malfunctions, you’ve accumulated significant days out of service, or your warranty period is nearing its end. It can also be helpful to reach out if the dealer refuses to perform calibration, blames “normal operation” despite clear symptoms, or the problem returns after software updates or sensor replacements. A consultation can help you understand your options, timelines, and next steps under California law without making any decisions before you’re ready.
This article is for informational purposes only, is not legal advice, and does not create an attorney–client relationship. Attorney advertising. Past results do not guarantee similar outcomes. If you believe your vehicle may qualify as a lemon, contact ZapLemon at (310) 489-3017 or https://zaplemon.com. A consultation is recommended to discuss your specific facts, documents, and potential options under California’s lemon law.