No doubt there would be a few that would try and pull something and another number who may plow headfirst in without thinking and misdiagnose the complaint but they would be in the minority.
There’s also a flip side to something like this that is very common and involves many things other than the A/C. Consider the following scenario.
Your MIL takes the car to the dealer for a no A/C complaint. The service writer types up the repair order, sends it to the dispatcher/warranty clerk who logs it into the system, and then dispatches it to a mechanic. The mechanic clocks in on the job, wanders around the lot, finds the car, notes the A/C compressor switch is not pushed in, and after verifying that is the only thing wrong with the car, leaves the car in the lot without even pulling it into the shop. He then fills out the paperwork, clocks off of the job, sends the paper to the dispatcher who goes back into the data entry, and then the paper is sent to the cashier who then pages the customer.
There’s a number of man hours, paper, printer ink, and say 5 to 10 minutes of the mechanic’s time involved in this. Assume the dealer has a labor rate of 100 dollars an hour and the mechanic puts a flag time of .1 or .2 hours (6-12 minutes). This means the customer would theoretically be billed 10 to 20 dollars for telling them they don’t know how to work the A/C controls.
What would most customers do in this case? They would raise hxxx over this.
The point then becomes one of “Well, it’s only 5 (or 10) minutes of the mechanic’s time…”.
Not quite. The dealer is footing those man hours involved in the process of that paperwork and the mechanic (who works on commission) is faced with the “Well, it’s only 5 or 10 minutes…” scenario many times during the workday.
It becomes cumulative and it’s quite easy to accumulate 2 or 3 free hours a day over things like this along with standing at the parts counter, waiting for someone to make up their mind on a repair, test drives, etc., etc.
Just food for thought anyway.