Illinois Used Car Lemon Law: The 15-Day Powertrain Warranty

If you bought a used car in Illinois and it broke down soon after, the rules protecting you are different from the ones that protect new-car buyers. This article is part of Illinois consumer protection laws: rights and enforcement, and it explains the one warranty state law forces most used-car dealers to give, why the “lemon law” does not apply, and the steps a buyer follows when a covered part fails.

Why the Illinois Lemon Law does not cover used cars

The law people call the “Illinois Lemon Law” is the New Vehicle Buyer Protection Act. By its own terms it applies to a “new vehicle,” and its statutory warranty period runs for one year or 12,000 miles, whichever comes first, under 815 ILCS 380/2. A car that was already titled to a prior owner does not meet that definition, so the lemon law’s repair-attempt and refund remedies are off the table for a used purchase.

The Illinois Attorney General draws the same line. Its guidance describes the Lemon Law as covering a new vehicle with a defect the dealer or manufacturer cannot fix in four attempts, or that is out of service for 30 or more business days in the first 12 months or 12,000 miles, and separately notes that Illinois law “now requires that some used vehicles be sold with a 15-day/500-mile powertrain warranty” (Illinois Attorney General, Auto Sales and Repairs). Used-car protection comes from that warranty, not the lemon law.

What the 15-day, 500-mile powertrain warranty covers

Since July 1, 2017, a licensed Illinois dealer who sells a used car at retail cannot disclaim the implied warranty of merchantability before midnight of the 15th calendar day after delivery or before the car is driven 500 miles, whichever happens first, under 815 ILCS 505/2L. Both the calendar and the odometer run from delivery, and any day the car sits broken, plus the miles driven to get it repaired, are excluded from the count.

The warranty is narrow. It guarantees that the car functions for ordinary transportation and is substantially free of a defect in a “power train component.” The statute defines that term precisely: the engine block, head and all internal engine parts, oil pan and gaskets, water pump, intake manifold, the transmission and all its internal parts, torque converter, drive shaft, universal joints, rear axle and all its internal parts, and rear wheel bearings. Air conditioning, electrical systems, brakes, and body problems are not covered.

Which used cars qualify, and which are excluded

Not every used sale triggers the warranty. Under 815 ILCS 505/2L, it does not apply to a vehicle with more than 150,000 miles at the time of sale, a title branded “rebuilt” or “flood,” a vehicle with a gross weight rating of 8,000 pounds or more, or an antique or collector vehicle. It also does not apply when the dealer provides its own express warranty at least as protective as the statutory one, or to forfeited vehicles sold at auction by the Illinois State Police.

Private-party sales sit outside the law as well. The warranty reaches retail sales by licensed dealers and sales at public auctions, not the car a neighbor sells directly.

There is one narrow route to sell a covered car without the warranty on a particular problem. The dealer can disclose a specific defect in writing and have the buyer sign a boldface waiver for that defect alone. A blanket “as is” sale that ignores the statutory warranty makes the purchase agreement voidable at the buyer’s option.

What to do when a covered part fails

1. Give notice within two business days of the deadline

   The buyer must give reasonable notice of the breach to the seller no later than two business days after the warranty period ends, under 815 ILCS 505/2L. A text to a number the dealer provided, a call or message to the phone number on the bill of sale, a letter to the address on the bill of sale, or an in-person visit all count as reasonable notice.

2. Let the dealer attempt the repair

   Before pursuing another remedy under Article 2 of the Uniform Commercial Code, the seller gets a reasonable opportunity to repair the car so it conforms to the warranty. Keep records of the dates the car went in and what work was done.

3. Pay your share of the first two repairs

   The buyer pays half the cost of the first two repairs needed to bring the car into compliance, capped at $100 for each repair. If the same defect returns for a second repair, the buyer’s share is still limited to $100. The dealer covers the balance.

4. Know the refund ceiling

   A seller’s total liability for repairs is limited to the purchase price paid for the car, refunded to the buyer or the lender in exchange for returning the vehicle.

How federal law and the Consumer Fraud Act fit in

A used-car dealer that chooses to give a written warranty also comes under the federal Magnuson-Moss Warranty Act, and the Federal Trade Commission’s Used Car Rule requires dealers to post a “Buyers Guide” window sticker showing whether the car is sold “as is” or with a warranty (FTC, buying a used car from a dealer). That federal sticker and the Illinois powertrain warranty operate together: the sticker discloses the deal, and state law sets the floor.

The powertrain warranty lives inside the Illinois Consumer Fraud and Deceptive Business Practices Act. A dealer who violates 815 ILCS 505/2L commits an “unlawful practice” under that Act, the same statute the Attorney General enforces against deceptive auto sales. A buyer whose covered claim is refused can file a complaint with the Illinois Attorney General’s Consumer Protection Division.