Management: Diagnostic Fee or Diagnostics Free – UnderhoodService

Management: Diagnostic Fee or Diagnostics Free

I can't tell you how many times I've heard the same lines from customers after I have diagnosed a problem: "Well, I could have done that myself," "I would have looked there for the problem if I had the time" or "I don’t know why you're charging me for something so simple."

I can’t tell you how many times I’ve heard the same lines from customers after I have diagnosed a problem: "Well, I could have done that myself," "I would have looked there for the problem if I had the time" or "I don’t know why you’re charging me for something so simple."

My usual answer is: “So if you knew what was wrong, why did you bring it to me to figure out?” 

With the advent of the computer age upon us, the car has become a rolling updatable, flash reprogramming software jungle of information. The cost of specialized scanners puts them out of reach for most consumers and a lot of small shops, which, in some ways, also places the shade tree mechanic on the endangered species list.


Defining the word “estimate” has been an issue for shops since day one. Should we charge to diagnose the car or should the estimate be free in hopes of selling the job? The main problem comes in the form of defining the word estimate.

One definition of an “estimate” is a list of all the parts and labor involved in making a repair, with the possibilities of adding additional parts and labor to the original estimate if other work is deemed necessary after the initial work has started.

Another definition of an estimate is a “guess.” To the customer, it might mean that with the chance the shop might get it right, but more than likely the final bill will be different than the original “estimated” costs.

The two definitions are different, but could mean the same thing depending on your perspective and wallet.

Diagnostic Money
What is a diagnostic? It is the process in which a technician is able to determine the cause or failure of a piece of equipment, vehicle or appliance. It is the process used to determine the root cause of a given mechanical or electrical problem that has become an issue with a vehicle, appliance or piece of equipment. Sounds the same as an estimate, doesn’t it?

Now we are starting to get to the real issue, money. The diagnostic process may take some time, and may even require a few sophisticated scanners, wiring diagrams and special tools.

Time is money as we all know,  and knowledge, expertise and experience are valuable commodities that should always be respected and monetized no matter what field you are in. Being able to sell and charge for time and experience is essential in the continuing financial stability of a shop or for that matter, any service oriented business.

Once the diagnostics have been completed, an “estimate” in the truest sense can be written and given to the customer for their approval. The customer should already be charged for the “diagnostic procedure” even if the the problem is  “intermittent” and the symptom did not occur during diagnostic testing.  The time has already been spent to figure out that there was nothing wrong.

That brings up another touchy issue.  For some reason, the customer feels cheated if you charge for nothing found. Now wait a minute; how was it determined that nothing was wrong? The  diagnostics process lead to that result.

If a technician can’t figure out a problem in a reasonable length of time, say an hour, then it’s possible the shop is going to be losing money if they kept him on that job. The next best thing would be to move him off that job, and put another tech on who might be able to figure out the problem in a reasonable amount of time. Of course, the shop is already behind the eight ball since the first tech didn’t get the job done, but in the long run, it will get done. There will be an estimate for the customer explaining the repairs needed.

I don’t know which is more of a problem, the shops out there not willing to charge for estimating, I mean diagnostic time, or the customer who doesn’t feel that it’s a necessary part of the process. Then again, these are not yesterday’s cars.

Then the problem isn’t the problem anymore, it’s the time spent looking for the problem that is the problem. To ease the customer’s woes, you could always give them a time table for future re-evaluations — 30 days is a good round number.

It has been my experience that one of the more common diagnosis is that of the customer. Many times, it is the customer’s lack of understanding of their vehicle, or dare I say, they are just another loose nut behind the wheel.

Charging for You
Now I’m not in favor of a free diagnostics (if you couldn’t tell already) and I’m not too fond of the free estimate. If there are any “man hours” that are part of any job, a “man” wants paid. If that “man” is working on a commission or flat-rate, I can assure you he is going to rush through the “estimate” in order to get to the real money of the job.

However, a diagnostic fee is a totally different thing. I don’t think I could have made a living without charging for the time it takes to diagnose some of the strange problems I’ve encountered over the years.

Some things were easy to diagnose, some took hours. But, I believe the standardization of a diagnostic charge at all automotive repair facilities could make things a lot easier for the customers to understand the complexities of today’s problem evaluations on modern vehicles.

It’s about time for some common practices on charging for diagnostic time for independents, dealers or even chain shops. From diagnosing a bad ball joint to a battery drain, a balanced set of standards everyone could agree on would change everything.

If all the shops in a demographic area charged similar diagnostic fees, it would lead to a more even playing field for everyone, including the consumer. It might even put an end to the “I can get it done cheaper down the street” escapades, making my drive home a whole lot more pleasant.


If I wasn’t in the business and didn’t know where to take my car, I would really like to know I’m getting quality work done at a fair price at any shop I went to.  If that didn’t happen, it then only comes down to a question of where to have the vehicle repaired at.

Everyone has their favorite doctor, dentist or restaurant, which is probably based on location, atmosphere or  just liking that particular place. Price is always an issue, and probably always will be.

How many times a day does your phone ring because you have some “price shopper” who is never coming to your shop because your price is higher than the last shop they called, even though they were referred by a “friend.”

No one wants to be the bad guy. Sometimes too much effort is put into the “Being nice to the customer” or the preverbal “Customer is always right” routine to get a customer in the door instead of selling them a diagnostic fee.

The old saying; “If the customer knew what was wrong, they would have fixed it themselves” still holds true today. But I’m talking about telling them what’s wrong with the vehicle, not how to fix it.

Common sense is the largest lacking component in all of these situations when defining to the customer what is an estimate and a diagnostic fee. In my opinion, once common sense is removed from the conversation, “stupid” takes its place. I wonder if I could estimate how many times this has happened. Maybe I could, but I better think about diagnosing it first. 

Scott “Gonzo” Weaver is the owner of Superior Auto Electric in Tulsa, Okla. and has owned the shop for 27 years. He was given his trademark nickname “Gonzo” while serving in the USMC. He is the author of the book “Hey Look! I Found the Loose Nut”, that can be purchased online at or at

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