How to prove a manufacturing defect in a vehicle before the consumer court

Many vehicle complaints fail not because the buyer is wrong, but because the defect was never proved. Manufacturers commonly answer that the problem was caused by the way the vehicle was driven or maintained, or that it was fixed under warranty. This post explains what evidence the Consumer Commissions look for, and how to collect it from the first day of trouble.

Why proof matters

An order to replace a vehicle or refund its price is a serious one, and Commissions make it only on firm evidence of a defect in manufacture. In a 2023 case involving a luxury car, Mercedes-Benz India v. Revathi Giri, the National Commission set aside an order to replace the car or refund its price, because there was no expert evidence of an inherent manufacturing defect and the reported problems had been attended to under warranty. That case was decided under the old 1986 Act, but the approach to proof is the same today.

1. The job cards

The single most useful document is the job card that the authorised service centre opens each time the vehicle comes in. A series of job cards recording the same complaint, within the warranty period and at low mileage, shows that the problem is persistent and that repairs did not cure it. Check each job card before signing:

• Your complaint should be written in your words, not shortened to “general check”.
• The date, the odometer reading and the work done should be recorded.
• Ask for a copy every time, and photograph it if a copy is refused.

2. An independent expert’s report

An inspection report from a qualified automobile engineer who is independent of the dealer is often what turns a strong suspicion into proof. The report should describe the inspection, the tests done, the cause of the fault and why it points to manufacture rather than use. Attach it to the complaint, with the expert’s qualifications and an affidavit, so that it can be read as evidence.

3. Testing ordered by the Commission

Where a defect cannot be decided without proper analysis or testing, Section 38(2)(c) of the Consumer Protection Act, 2019 allows the District Commission to take a sample, have it sealed and send it to an appropriate laboratory, which is to report within 45 days. The complainant deposits the testing fee. Either side can object to the report and be heard on it. For a vehicle, this usually means inspection of the vehicle or the failed part by a testing agency or an expert the Commission appoints.

4. Your own records

• The invoice, delivery note, warranty booklet and owner’s manual.
• Photographs and videos of the fault as it happens, such as warning lights, smoke, leaks or noises.
• Diagnostic or scan reports, if any were taken.
• Emails, chat messages and complaint numbers from the dealer and the manufacturer, including any written reasons for refusing warranty.
• A simple diary of when the problem occurred and how it affected you.

Messages, photographs and emails are electronic records. When they are filed as evidence, the Bharatiya Sakshya Adhiniyam, 2023 requires a certificate about how they were produced and stored (Section 63), so keep the original phone or email account.

When the defect speaks for itself

Some failures need little expert explanation. In Hyundai Motor India Ltd. v. Shailendra Bhatnagar (20 April 2022), the front airbags of a car did not open in a frontal collision. The Supreme Court upheld the order to replace the car and pay compensation, observing that a buyer is entitled to expect airbags to open in such a crash and need not understand the physics of a collision. It also held that time to complain ran from when the defect surfaced, the date of the accident, and not from the date of purchase. The case was under the 1986 Act.

Keep the vehicle available

If the case may need an inspection, do not sell the vehicle, change the failed parts at an outside workshop, or modify it while the dispute is pending. If a part must be replaced, ask for the old part to be returned to you, sealed and labelled.

Common questions