Spare part installations expose workshops to increasing risks as more customers purchase their spare parts from online shops. Therefore, product liability law and its applicability to spare parts should be fully understood by businesses to avoid any legal implications. This guide will explain who is responsible for defective products, the law governing this and why it is important to use genuine spare parts.

Who is Liable for Defective Products?
Spare parts on the Internet are often cheap, but have you ever thought about where they come from? This is an important question, especially for workshops. Whether a spare part is purchased by the customer or directly by the workshop, it is the workshop's responsibility to ensure that the part is flawless before installation. If a defective part is installed and later contributes to an accident or issue, the workshop could face legal liability under certain conditions.
For instance, the workshop may be held liable if:
- The spare part originates from an unverifiable source.
- The manufacturer or supplier of the part cannot be identified.
- The part is purchased from outside the European Union.
In these situations, product liability law may treat the workshop as the manufacturer, significantly increasing the legal risks. This is particularly critical when dealing with safety-related components where the consequences of failure could be severe.
Our Recommendation: To protect themselves and their customers, workshops should always use genuine spare parts from reliable and verified brands. By doing so, the manufacturer assumes responsibility for the liability, ensuring that the workshop remains safeguarded from potential legal and safety issues.

What Is Product Liability for Spare Parts?
Product liability law means that manufacturers and sellers are required to make sure that any products they offer are safe for use. In the case of spare parts, the manufacturer is liable for any errors that may be found in the product.
But if a part fails because of defects and it is impossible to identify the manufacturer or supplier it came from, then the workshop that installed it could be held responsible. This is especially true if the part was purchased from an unauthorised vendor or if it was purchased from a non-EU-based company.
Key takeaway: Workshops must understand that installing unverified parts could expose them to product liability claims.
Can Workshops Be Held Liable for Customer-Supplied Parts?
Yes. Even in cases where a customer arrives with their own spare part, the workshop takes the liability of confirming that the part is serviceable and compatible with the vehicle that it is intended for.
If the part is defective or leads to an accident, the workshop can be held liable—especially if the part is sourced from an unverifiable or non-branded.
Best practice: Before installation, check the legitimacy of customer-supplied parts, no matter where they’re sourced from.
What If the Manufacturer Is Unknown?
When the manufacturer of a spare part cannot be identified, or if the part is from outside the European Union, the workshop could be treated as the manufacturer.
This makes the workshop legally responsible if the part causes any mishap, especially with safety-critical components like brakes or steering systems.
Tip: Always install genuine spare parts from trusted suppliers with clear origins, since the risks associated with unknown manufacturers can be high.

Why Should Workshops Use Genuine Spare Parts?
Using genuine, branded spare parts from verified suppliers offers several advantages:
- The manufacturer takes full responsibility for any defects
- These parts are designed to meet strict quality and safety standards
- Genuine spare parts typically come with warranties that protect both the workshop and the customer
In contrast, non-branded or counterfeit parts don’t offer this level of assurance, exposing the workshop to liability risks.
What Are the Risks of Using Non-Branded or Counterfeit Spare Parts?
Non-branded and counterfeit parts can pose several risks:
- Lower quality and reliability: These parts often don’t meet the required standards for safety and performance.
- Lack of accountability: If the part fails, holding anyone responsible becomes difficult.
- Legal exposure: If a workshop installs a counterfeit part which causes damage or an accident, the workshop is likely to face significant legal consequences.
Remember: The potential cost of using cheap, unverified parts far outweighs the savings in the long run.
Nice-to-know

Here are some best practices workshops can follow to minimize liability risks:
- Always verify the authenticity of spare parts before installation
- Keep records of where parts were sourced from, especially for customer-supplied parts
- Ensure that all parts come from reputable suppliers within the European Union or trusted sources
- Use genuine branded parts wherever possible to reduce risks
By following these guidelines and understanding , workshops can protect themselves from legal complications and ensure the safety of their customers.
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