Are diagnostic charges covered by Ford Protect? The short answer is "Yes", but you may still be told that you are potentially responsible for paying diagnostic charges prior to a dealer touching your car. The reason is that diagnostic charges are only paid by your warranty if the claim is covered. If it turns out that your repair is not covered, you ARE responsible for diagnostic charges.
Let's suppose that your vehicle has a starting problem. The technician determines that it needs a new starter. The warranty time guide may say that that labor operation should take a total of 1.2 hours. This would be further broken down into .3 hours for diagnosing the problem and .9 hours for actually replacing the starter. The dealer would be paid 1.2 times their posted hourly labor rate and the technician would be paid 1.2 times their hourly rate regardless of how long the entire repair actually took.
As another example, let's suppose that your dvd player is not working. You bring your vehicle to the dealer. You tell the Service Advisor that your dvd player is not working and ask if it is covered. The Service Advisor says that the dvd player is covered and therefore the diagnostics are covered. You leave your car and go off to work.
The Service Advisor will usually tell you when you drop your car off that you are responsible for diagnostic charges, if the repair is not covered by your Service Contract. You may even be asked to sign a repair order that clearly states that you are responsible for diagnostic charges.