DLM Distribution

What Is the Magnuson‑Moss Warranty Act?

The Magnuson‑Moss Warranty Act, enacted in 1975, is a federal law that governs consumer product warranties. Found in Title 15, Chapter 50 of the U.S. Code (§§ 2301–2312), the law ensures that manufacturers and sellers of consumer products over $15 provide clear and fair warranty terms. It was designed to prevent deceptive warranty practices and ensure consumers are not misled.

For vehicle owners, this means manufacturers and dealers must honor warranty obligations even when aftermarket parts or services are involved—unless they can prove the part directly caused the failure in question.

What the Law Means for You

Under 15 U.S. Code § 2302(c), a manufacturer cannot require that only branded parts be used to maintain warranty coverage—unless those parts are provided free of charge.

This means you are legally allowed to:

-     Add aftermarket accessories

-     Upgrade vehicle systems

-     Use non-OEM replacement parts

-     Customize appearance and utility

...without voiding your warranty. Denial of warranty coverage is only permissible if the manufacturer can prove that your modification directly caused the issue. This standard is clarified in FTC guidelines interpreting the Act.

Key FTC Guidance:

“The manufacturer or dealer must show that the aftermarket or recycled part caused the need for repairs before denying warranty coverage.”
— Federal Trade Commission: Business Center – Warranty and Aftermarket Parts

Handling Warranty Disputes: When a Shop Tries to “Blame” Accessories

Some OEM service departments or dealerships may attempt to attribute a failure to an aftermarket part—even if there’s no valid connection. This can be financially motivated, as customer-pay jobs often result in higher payouts than warranty-covered repairs.

If this happens:

1) Stay calm and professional. Ask for a clear explanation of how the aftermarket part allegedly caused the issue.

2) Request written documentation. You have the right to a written statement outlining the reason for the denial.

3) Ask for proof. Under the law, the burden of proof is on the manufacturer—not you.

4) Get a second opinion. Another dealership or independent mechanic may disagree with the diagnosis.

5) Assert your rights. Let them know you are aware of your rights under the Magnuson‑Moss Warranty Act.

6) Elevate your concern. You can contact the vehicle manufacturer’s support team or file a complaint with the FTC.

How to Ensure You're Protected

To keep your warranty intact and your rights protected:

- Save records. Keep receipts and installation notes for all aftermarket upgrades or repairs.

- Use qualified professionals. Ensure installations are done properly and don’t interfere with vehicle safety systems.

- Know your warranty. Review your warranty booklet and owner’s manual.

- Track communication. Log conversations and keep emails or service records if issues arise.

Why This Law Matters

The Magnuson‑Moss Warranty Act provides critical protection for consumers who want flexibility and fairness. It ensures that your ability to maintain or personalize your vehicle does not void the broader warranty unless the manufacturer can provide clear and specific proof of causation.

This law promotes honest service practices, fair treatment, and accountability from manufacturers and service providers alike.

When to Get Help

If you're unable to resolve a warranty dispute, here are your options:

- Contact the manufacturer’s customer service department.

- File a complaint with the Federal Trade Commission (FTC):

- Consult a consumer protection attorney. Many states have lemon laws or similar statutes that align with federal protections.

In Summary

Installing aftermarket parts or accessories does not automatically void your vehicle warranty. Under the Magnuson‑Moss Warranty Act, manufacturers must prove a direct connection between your modification and the problem in question to deny coverage.

By understanding your rights, maintaining proper documentation, and communicating clearly, you can protect your investment and navigate repairs with confidence.