In the USA is it legal for a manufacturer to:
- warrant a product in a way such that only they can test a pass/fail without disclosing the test criteria used
- charge the consumer to run the test
- require paid (software) upgrades on the product in order to run the test?
For example, some electric car manufacturers offer a warranty on the vehicle's battery capacity retention being above a certain threshold (typically 60-70%) through the 8 year federally mandated warranty period because batteries naturally lose capacity over time and use.
However, exact battery capacity is difficult to measure so the manufacturers will dictate that an authorized dealer must perform a test for it. In some cases there is little description of the test beyond the dealer plugging the car into a computer, doing something and the computer generating a "pass" or "fail" response with no further explanation of what determines a pass or fail.
Additionally, some people report that their dealer required that the car's software be updated (for a fee) prior to performing said test.
So, is it legal for a warranty to hinge upon undisclosed criteria? Is it legal to charge money to perform such a test? And is it legal to require an additional purchase (software upgrade) to perform such a test?
Edit to add two points that may be relevant:
Does it matter if a dealer themselves does not understand what the test does and that the test computer is running the manufacturer's software which is the only way to determine a pass/fail?
There are various ways to approximate battery capacity, including charging to full, and driving until the car stops to measure mileage however that is not only impractical because you may run out of charge in an undesirable location on a roadway but it also can vary substantially due to driving efficiency (are you driving uphill the entire time?). Because of this, no guarantee is in "miles of range" and any possible methods of capacity are an approximation. The manufacturer claims that only a dealer can make a warranty determination but the dealer seems to claim that it is ultimately the manufacturer's determination.