Lemon Law Firm on Common Manufacturer Defects

When a new or used vehicle spends more time in the shop than in your driveway, it’s natural to wonder whether California’s lemon law can help. At ZapLemon, we regularly hear from drivers dealing with recurring problems that just don’t get fixed. Below, we explain common manufacturer defects that trigger lemon law questions, and what to document before you call us so we can evaluate your situation efficiently. This post is educational and general in nature—every case is different.

Common Manufacturer Defects Under California Law

California’s lemon law—part of the Song-Beverly Consumer Warranty Act—generally applies when a vehicle covered by the manufacturer’s warranty has a defect that substantially impairs its use, value, or safety, and the manufacturer or its authorized repair facility can’t fix it after a reasonable number of attempts. “Manufacturer defects” are problems that trace back to design, materials, or assembly—not normal wear-and-tear or damage from accidents or modifications. The law can apply to new vehicles and, in many situations, used vehicles that are still under the original factory warranty or certified pre-owned warranties.

Some of the most common defects we see involve the powertrain and drivability. Examples include engines that stall, overheat, or burn oil; transmissions that shudder, slip, or hesitate; and coolant or oil leaks that persist despite multiple repairs. We also see braking and steering issues such as soft brake pedals, premature rotor/pad wear, ABS warning lights, power steering loss, or alignment that keeps drifting. Safety-related defects can include airbag or seatbelt warning lights, “check engine” lights that never stay off, and malfunctioning electronic stability control.

Modern vehicles add layers of electronics that can introduce new problems. Owners frequently report infotainment screens that freeze or reboot, backup cameras or Bluetooth that fail intermittently, power window or door lock glitches, and parasitic battery drains. Advanced driver-assistance systems (ADAS)—like lane keep assist, adaptive cruise control, collision warning, and automatic emergency braking—may give false alarms or simply stop working. Electric and hybrid vehicles present their own patterns: rapid high-voltage battery degradation, charging errors, software updates that reduce range or performance, and faulty onboard chargers or inverters. If these issues persist after multiple dealer repair attempts, or the vehicle is out of service for extended days, it may be time to ask questions about your rights.

California has a helpful “presumption” that can apply within the first 18 months or 18,000 miles, such as when a vehicle is out of service for more than 30 total days, needs four or more attempts for the same non-safety defect, or two or more attempts for a defect that could cause serious injury or death. Even if you’re outside those mile/month markers, you may still have rights under the statute—those benchmarks just make certain proofs easier. Warranty coverage is key: the problem typically needs to arise and be presented for repair while the manufacturer’s warranty is in effect. Usage, aftermarket modifications, or neglect may affect coverage. Because every situation is unique, a consultation is the best way to understand how the law may apply to your facts.

What to Document Before Calling ZapLemon for Help

Good documentation is often the difference between a frustrating back-and-forth and a clear path to answers. Start by gathering every repair order and invoice from the dealer or authorized service center. Make sure each document shows the date, mileage, your reported symptoms in your own words, the technician’s findings, and what parts and labor were performed. If the problem is intermittent, ask the service advisor to write that down and note the conditions (speed, temperature, road type) when it happens. Keep photos or short videos that capture warning lights, noises, leaks, or infotainment/ADAS glitches.

Next, pull together your purchase or lease agreement, the window sticker if you have it, and the warranty booklet. Save emails and texts with the dealer and manufacturer, including case numbers from any corporate customer-care calls. If you received loaner vehicles or rental reimbursements, keep those receipts and note the dates the car was out of service. Towing invoices and roadside assistance records are helpful, too. If there are recall letters or technical service bulletins (TSBs) you’ve seen, collect those as well.

A simple timeline can make your story crystal clear: list each repair visit, the complaint (e.g., “transmission shudder 20–40 mph”), the dealer’s fix, and what happened afterward. Check your warranty status and any open recalls on NHTSA’s website using your VIN. Avoid clearing diagnostic codes or disconnecting the battery before a service appointment, because that can wipe data the technician needs. If you need to communicate concerns, try to use email so there is a record; California generally requires consent from all parties to record phone calls, so when in doubt, keep it written. With this packet ready, ZapLemon can review your file and discuss whether your vehicle’s history points to a potential lemon law claim.