Warranties and aftermarket parts

There was an interesting post on Roadfly recently, which is worth reading for anyone considering aftermarket parts on their MINI:
The MINI warranty on a component is void due to a modification where the modification, alteration or installation of a non-approved aftermarket part was responsible for the failure … In the case of electrical accessories, such as alarms, radios, amplifiers, radar detectors and telephones, extensive damage to the vehicle’s wiring harness may occur when these accessories are installed …
The MINI Division of BMW NA has been supplied with the Vehicle Identification Numbers of some vehicles that have reportedly been modified. These VINs have been entered into our computer system and will provide you with the message to call the Warranty Department or a detailed text of the modifications performed …
The poster kept his identity secret, and my local dealership does not recognize the memo, but does recognize the sentiment, and tells of frustrating diagnosis sessions eventually traced to badly installed or faulty aftermarket parts.
This issue is relevant to all cars, not just MINIs, and is worth remembering when choosing to add aftermarket parts to your car – at a minimum, be very confident in both the product and the installer!

Full text of message posted on Roadfly:
The MINI warranty on a component is void due to a modification where the modification, alteration or installation of a non-approved aftermarket part was responsible for the failure.
MINIs are highly sophisticated. The various components, both electrical and mechanical (i.e., suspension and steering), have been integrated and designed to work collectively. That is why installation of non-approved accessories and/or modifications to existing components in the vehicle may have adverse effects on its operation and safety.
In the case of electrical accessories, such as alarms, radios, amplifiers, radar detectors and telephones, extensive damage to the vehicle’s wiring harness may occur when these accessories are installed. The damage may occur when poor connections are made for their power and ground leads without any concern for the circuit being tapped. Even the routing and placement of these accessories and harnesses in the vehicle can effect other components due to certain electromagnetic interference. Examples of these effects are: whining heard through the sound system, a dead battery and unusual/sporadic operation of electrical systems found on the vehicle. MINI makes special efforts to seal the vehicle against water from entering the interior in particular through the firewall. Grommets are specifically designed for this purpose. If a grommet has been perforated due to aftermarket installations, water may drip onto electrical connectors inside the car.
Modifications to the body structure of the vehicle are also of great concern since the structural integrity and crash worthiness can be greatly affected. An example of this is the installation of speakers into non-approved speaker openings.
We must also strongly advise against modifications to the suspension and engine. Typical suspension modifications are: springs, struts, shocks, wheels and tires. Typical engine modifications are: air intake system, throttle body, supercharger or pulley, and exhaust system. Installation of such items that are not MINI approved can have a direct effect on the vehicle road-worthiness and response in evasive situations.
It is our responsibility as an automobile distributor to notify you, as a dealer of our product, that performing such non-approved installations/modifications can place the burden of the vehicle’s worthiness and safety upon you. In addition, you must be made aware that such non-approved modifications and installations may effect the validity of the MINI New Passenger Car Limited Warranty. We feel that our current and future offering of accessories meet the needs of our customers.
Installation of an aftermarket part or accessory does not necessarily void the vehicle warranties. The scope of possible alterations is very large and therefore a listing of all situations would be impossible. Common sense must prevail and in a questionable situation the dealership’s staff should ask for assistance by calling the Warranty Department. In addition, information on the dealer’s responsibilities can be found in the Warranty Policy and Procedures Manual.
Reported Vehicles
When unknown, modification of a vehicle can complicate troubleshooting and may result in multiple repair attempts. The MINI Division of BMW NA has been supplied with the Vehicle Identification Numbers of some vehicles that have reportedly been modified. These VINs have been entered into our computer system and will provide you with the message to call the Warranty Department or a detailed text of the modifications performed, when inquired upon using “Delivery Date Inquiry” or “Vehicle History Inquiry” via MINI DCSNet.
The purpose of flagging the VIN is not to be misinterpreted. By obtaining the details of the modification, an easier diagnosis of the vehicle can often be made. The Warranty Department will define, based on the information supplied by the MINI Dealer, whether or not the modification should or should not be covered under the MINI New Passenger Car Limited Warranty, Maintenance Program or other coverage.