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Why Auto Shops Charge A Diagnostic Fee

Do you offer free diagnostics? This is a question we get asked often. It’s a valid question that doesn’t have a simple yes or no answer.

First off, we have to define what a diagnosis is. A full diagnosis requires an auto repair tech to identify the specific root cause behind why something is not working appropriately. For example, if you drive in with a flat tire and a tech says “You have a flat tire”, this wouldn’t be a full diagnosis. A full diagnosis does more than just describe “what” the issue is, it explains the “why” behind an issue. It not only takes time, unified effort, and advanced diagnostic repair equipment, it also ultimately saves a ton of time and money in the end.

Think of it like going to the doctor. If the doctor does a surface level check and diagnosis your symptoms without treating the root cause – or if they diagnosis the root cause incorrectly – you’ll have to return over and over again, ultimately spending more time and money to try to find the true cause until you have a solution. And you have to pay for all the testing, regardless of if it discovers the problem and helps find the correct treatment.

Similarly, imagine going to an auto repair shop that offers a free diagnosis, keeping in mind that free guesses usually cost more. For example, your check engine light comes on because there’s a problem with the air-fuel ratio. Your free inspection suggests that the issue is a faulty oxygen sensor, so you replace all the oxygen sensors. You spend a thousand dollars on oxygen sensors only for the check engine light to come back on. The problem is still there, now 4 figures and several hours later.

A diagnostic fee is simply the fee paid in order for the auto shop to be able to understand the “why”, the root cause  behind why your vehicle isn’t working the way it should. Our shop has invested in hundreds of thousands of dollars of top of line diagnostic equipment simply because we have seen the harm that poor diagnostics does over the years, and we deeply believe that pinpoint diagnostics is one of the most valuable services we can offer as a mechanic. No one wants to waste time and money, lost in a web of confusion, to fix a vehicle that may or may not work.

It takes YEARS of experience, certification, talent, and equipment to properly diagnose issues in your vehicle. In addition, it takes a lot of work to maintain diagnostic equipment and consistently keep it up-to-date on training to accurately diagnose the cause of problems.

As another example, if the check engine light comes on, there are hundreds of diagnostic codes that can be triggered, almost all of which require testing to determine why they are being triggered. Here at Main Street Mechanic, our ASE-Certified auto repair technicians use top of the line diagnostic tools to identify the problem. We’ll pinpoint the EXACT cause of the issue in way less time, sticking to our motto of “we test, not guess!”

We want our customers to know that finding the root cause of an issue takes far more time, training, tools, and experience than simply seeing an issue’s symptoms – similar to a doctor that only tries to treat the symptoms rather than the root cause. An accurate diagnosis is essential for auto shops too – it gives us clear direction on the fix that needs to be done. Our goal is to help you avoid the frustration of having to take additional time to return to an auto shop and pay for additional repairs.

One thing we’re always trying to accomplish as auto mechanics is to explain what’s happening in your vehicle in terms that anyone can understand. We don’t want to confuse you, talk down to you, or use a bunch of technical terms that leave you scratching your head. However, because of this, most people have no idea how complicated their vehicle is. Did you know that the computers inside the newer Ford F-150’s contain more lines of software code than the space shuttle, an F-35 fighter jet, and the whole Windows 10 operating system combined? We have all this new technology to thank for automatic headlights, lane departure technology, and so on. However, this makes diagnostics even more complex – and important! Out of thousands of possible issues, high quality diagnostics are well worth the modest fee required to pinpoint the exact issue and fix your vehicle the right way the first time.

Why Choose Main Street Mechanic in American Fork?

In addition to our cutting edge diagnostic equipment and certified technicians, we also offer:

  • 3 year / 36,000 mile warranty on parts and labor
  • Free roadside assistance for 12 months/12,000 miles following every paid service
  • Before and after hours drop off and pick up
  • Free customer shuttle to and from home/work/school
  • The only AAA Certified auto shop in North Utah County
  • Voted Best Mechanic of Utah Valley 3 Years in a Row!

Whether you need repair, maintenance, diagnostics, or inspections, make sure to come into Main Street Mechanic in American Fork. Vehicle repair and maintenance has never been so easy. We provide the highest quality service for all vehicles, both foreign and domestic. If you have a question about any service we offer, or if you would like to make an appointment, please don’t hesitate to call us at (801) 756-2661 or stop by the shop!





7:30 AM - 6 PM


337 West Main Street
American Fork, UT 84003


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