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One Diagnostics, Two Diagnostics, Three.... the song and dance of diagnostics.

One diagnostics, two diagnostics, three

The budget conscience customer at a repair shop asks, “Why do you charge so much for diagnosing a car? The machine does all the work. I’d rather just take my car to one of those places that offer free code checks.” The mechanics answered, “If those “machines” do all the work and those free places can tell you what’s wrong, why are you here?” It’s the typical song and dance of the one diagnostics, two diagnostics, three.

Apparently, I was misinformed as to how or what knowledge is necessary to diagnose the modern car. It seems, to some people, that all you have to do is hook up a scanner and the answer pops out like bread in a toaster. If so, why do most of these folks that head for these free code jockeys, still end up going to next read-code-change-part shops before a “real” mechanic finally figures out the problem?

Of course, you have to consider where this information about diagnostics is coming from. It’s a safe bet that neither captain code reader or his first mate cheap skate customer, have any high opinions that a trained professional mechanic is needed to find out what’s wrong with the land yacht. The opinions vary, but you can basically whittle them down to just three variations especially when it comes to diagnostics.

A – “All mechanics are alike”
B – “Always go with the cheapest mechanic you can find because they all have the same scanners and tools.”
C – Combine A and B.

It’s the term “diagnostics” that has several different meanings too. The charge for the diagnostics is always a question that someone will have, but I’ve never had anyone ask me, “What makes your diagnostics better than the next guys?” Just in case I ever had to answer that question, I’ve divided up this song and dance of diagnostics into three categories. So here goes, diagnostics, and a one, and a two and a three….

1. Be the code commander at one of those “free read” places, and grab your low-end-can’t-do-much-else-but-read-generic-codes and give your interpretation of what the display is telling you after your brief instructional lesson on the use of the tool to an even less informed consumer.

2. Be a code jockey at a more professional shop than your local parts store code commander ever could possibly imagine of being, and grab your high end scanner but only to use it like a code reader.

3. Actually testing the component or system that is coded and determining what the failure is with the aid of a scanner and other various tools of the trade.

The big problem that I see is that some people that have the same misconceptions that all mechanics are equally trained also have mistakenly determined that all scan tools are the same. Code reading is one thing, giving your opinion of the meaning of said code is another. Trying to diagnose by just reading a code is the real problem.

It still surprises me when someone questions the diagnostic fee, or asks, “Now you’re going to take that off the bill if I have the work done right?” Answer that question with a no and you’re liable to see a majority of those type of customers walk out the door. Say yes to the question and you’re into a situation that after you’ve spent time on finding the source of the problem that the estimated repair is going to run more than the customer wants to put into the car, and now they decide not to have the work done. All the time you just spent on the car is lost dollars that you’ll never recover.

I’ve tried it both ways over the years and I’ve come to the conclusion that I’m better off getting paid for the use of my scanners, diagnostic charts, meters, scopes, and various other tools needed to perform the correct procedures and tests than I am of letting all my efforts slip out the lobby door.
What’s the solution? Everybody has their own opinion as to what works better. Quite frankly, I think the only way it will ever change is with time. When enough time has passed and less and less repairs can be made without solid and proper diagnostics maybe then it won’t be such a big hassle.

For the here and now, maybe I should offer diagnostics as a “One, and a two, and a three” types of diagnostics. But, I’m no jockey and I’d make a terrible captain so I might offer different code diagnostics but that doesn’t mean I’m going to like it.

As it is now, most everything such as turn signals, engine performance, theft systems and the like all go through more than one computer module. Coding is taking on a whole new era of diagnostics. One thing can lead to two and two can lead to three. That’s where more in-depth diagnostics plays a major part in solving an issue with the modern car more than just read a code.

I wouldn’t put it passed the engineers to monitor balljoint wear with a sensor, or even tie rod ends in the near future either. All those wearable items on a car could eventually be monitored in some form or fashion. Then, when a car comes in for a front end alignment it won’t be so much the technician putting it on the alignment machine right off the bat, they would have to start the diagnostics off with a scanner. There would be less of the customer coming in that tells the mechanic that the last shop said they needed a laundry list of suspension parts when nothing checks bad at the next shop.

For the most part, if you’re reading this and you’re a shop owner or tech you’re probably nodding your head right about now. You’re probably saying to yourself, “Been there, done that.” Yea, “we” know what it takes to diagnose some of these problems but what “we” need to let every consumer know that it takes more than a code jockey or captain code reader to diagnose their car. Diagnostics isn’t as simple as “A one, and a two, and a three”.

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Good one Gonzo, When a customer comes to me with a code someone or themselves have pulled and say they know the problem, I ask them why did they not fix it them selves if they know the problem.. Then I put it in layman's terms as easily as possible for them to understand. I let them know there is a diagnostic charge and that will stick and that my scanner costs a little more than the 19.95 they paid for the one at the parts store and there is a good reason why.

I need to be able to see what all sensors and actuators are doing understand what the computer is seeing and how it is reacting.. I put it to them like this ...


A code you pull from the computer is like a number on a door, you open that door then there is a huge hallway lined with doors all with numbers say 50 doors per side, now behind one of those doors is the problem, we can open each door one by one say for 50 bucks each or you can let me diagnose where the problem lies and open just that one door. Which would you like me to do?

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yes I have heard the story just today as Pat Goss explained on his radio show today why a free diagnostic code reading, usually turns out costing more then if you just would have paid for the diagnostic in the first place. They read the code sell you a part and clear the code and your on your way as a happy customer, but not for long. Then later on your back with the --money light-- on "check engine light" on again, ready to spend more money!

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I've tried it both ways... Paid and unpaid. From a mechanic standpoint, paid is the only way to go. But from a business marketing standpoint, there's a benefit to the the "take it off if you get the work done". It's all in #s, and wording. And yes you will need to be creative AND sleesy at times. That's why the marketing way of looking at it solely is hard to do. But I've found a nice in between for MANY scenarios: Mark the repair labor hours up, require customer purchase parts from you in order to get the "free diagnostics"... U make part money, cap the free diagnostic time to 1 hour, or cap on the type of diagnostic (electrical not included, removal of parts not included). All of these worked for me but it's all in the wording. But I'll tell you what works BEST.... Give them something else for FREE that they value in exchange for paying you for diagnostic. Example : FREE towing with paid diagnostic and repair (up to 20 miles radius). I grabbed MANY folk with this one. The tow was $50, my diagnosis started at $85....and i marked up the labor to compensate for the difference.... I win, they pay regular price, car is purring.

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A code you pull from the computer is like a number on a door, you open that door then there is a huge hallway lined with doors all with numbers say 50 doors per side, now behind one of those doors is the problem, we can open each door one by one say for 50 bucks each or you can let me diagnose where the problem lies and open just that one door. Which would you like me to do?I


I'll trade you. I tell the customer that my guy "interprets" the codes. If he gets 7 codes, for example, many times he notes that this code caused this one and this code caused this one, therefore you only have 3 codes. He just saved you an oxygen sensor.


Your free code reader guy would have sold you an oxygen sensor and then had an excuse ready why that didn't fix it. You ALSO need a ... and maybe a ...

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newport5, thanks. I won't go in to it any deeper because is will just become a rant on my behalf about how the industry has really been hurt by free code readings and the lack of trained mechanics along with all the internet "sensations" and back yard mechanics that have given the general public these ideas that there is a machine you hook up to the car and it "tells" you what is wrong along with the code that "tells" you what is wrong. Unfortunately this industry has taken a huge hit by bad information given out by uneducated individuals . It will take a long time if ever for the industry to rebuild from this.

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