The Auto Scan Tool

misfire trouble code set

Information about the Auto scan tool by Master-Tech Mark. You can skip the reasons to own a car scanner and scroll down to read specific articles on check engine light common problems. There are also helpful articles about scan tool operation further down this page.

On the fence about getting a scanner? The answer to this question is to follow. Having an auto scan tool can help save money and time by avoiding a trip to the auto repair center. It's common these days to have the service engine soon light pop on. The monitoring system that activates the warning is sensitive. If you fix the problem the lamp stays on until reset. Resetting check engine lights is a simple procedure. I keep an Actron 9125 code reader in my glove box.

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These type of pocket scanners make the task inexpensive and easier then you might think. Pocket scanners can read and erase codes with one or 2 button operation and comes with detailed instructions on how to use it.

There is usually an included code book (sometimes on CD) that will let you know what codes set in memory stand for. There are a few nuisance codes and some that may cause damage to your engine or related systems if not addressed.

For this reason I think knowing the set codes is important. You really don't want to turn off the light without knowing why it's on. In my opinion this is a great Diy auto repair for beginners. First some background on what turns on the service engine soon light and why it exists at all.

Basically the Federal Government wants to notify the driver that the vehicle may be contaminating the atmosphere. Yes the main function of this light is for emission system compliance. The dash light comes on to notify drivers something might be wrong.

Sometimes the code relates to a serious failure. But the light shines just as bright if it's a minor malfunction or intermittent car problem. If you have your own auto scan tool you can answer the number one question in most peoples mind when check engine lights pop on.

The question is why is this light on and how can I turn it off. An auto scan tool can reset the codes therefore turning off the light and tell you why it came on in the first place. This brings me back to reason number one for buying a scanner. When the service engine soon light comes on you can perform the first steps of diagnosis yourself.

After a few times using the tool for DIY check engine light repair you will no longer fear the dreaded warning light. In fact why not be a hero and also help family and friends with this common car problem!

All you have to do is plug in the automotive scanner, turn the key on and hit the read button. This will pull codes from the computer that often point towards the malfunction.

It will then give you the option to reset the check engine light with a button push. I recommend you write down the code number before you hit the erase button even if you have a good memory. This way if the light comes back on you can see if it set the exact same trouble codes.

Why Have a Scan Tool Reason Two

image of auto scan tool kit

When a service engine soon light is turned on, and you take your vehicle to the dealership. The first thing they do is connect a scanner to retrieve the code.

They take this code and look it up in their auto service manual. In most cases the first step in diagnosing any code is to clear or reset the check engine light code and see if it returns as a hard failure.

If the auto repair center clears the code and it does not return the problem may be intermittent. In this scenario you are often charged at least one-hour diagnosis for very little auto repair help. If you had your own automotive scan tool you would be able to retrieve and record the codes, then clear the computers memory. Then drive the vehicle to see if it was an intermittent problem all by yourself.

If the service engine soon light does not come back on. You have just repaired your vehicle in a span of about 10 minutes. You have also just avoided a trip to the auto repair center (priceless).

If the service engine soon light comes back on you will be able to reconnect the auto scan tool and verify the same code as been set.

Now take the vehicle to a repair center with the information that the auto scan tool has provided for you. Or try diagnosing the code yourself using an online repair diagram such as All Data DIY. I put a page together and shot a screen capture video of how it works right here. This can cut down on the initial diagnosis costs, because you've already cleared the codes and done the first major step of diagnosis for the auto repair center.

Reason Three to Get a Scanner

One common reason for the service engine soon light to come on is the number one nuisance code for fuel system vapor leak. As of 1996 federal emission laws require the manufacturer to lightly pressurize the fuel system to check for vapor leaks.

The computer performs a pressure test automatically when you turn the key on. There are a lot of parts involved in the test. Things like spiders building nests in vent lines can turn the light on.

Or have you filled up the gas tank and not tightened the cap? The ECU can see this as a vapor leak and illuminate the service engine soon light. These scenarios are not on every vehicle but on many. This is one of those Nuisance Codes that have become the poster child for owning some kind of check engine light scanner.

To me the worst part about the OBD 2 system is that when the service engine soon light is turned on, it stays on until the code is cleared. Even if the problem that turned on the light is gone.

The Actron 9580 auto scan tool on the left is a little more advanced then the code reader mentioned at the beginning. It can tell the operator if the code is a present failure or a history code and provides common solutions to set codes through the enhanced features. You can plug in this scanner and pull the code to see if it's the fuel system leak code.

You can then go around and check the vehicle gas cap for tightness and then clear it. Then continue to operate the vehicle as you would normally for several days. If the light stays off, once again you have just repaired your own car in a span of about 10 minutes.

image of autel scanner

If the check engine light does come back on again, you have still learned something plus saved yourself time and money in the form of initial diagnostic charges.

I have been using diagnostic equipment for the last 25 years. In 1996 the federally mandated deployment of OBD 2 changed the the auto scan tool. Below you will find a few helpful articles on the subject of DIY check engine light repair.

Give this auto repair resource page a bookmark or share with a friend. Come back to read the helpful articles that address particular problems below!

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Information on Scan Tools and Check Engine Lights

Car code readers have become easy to use and a lot cheaper to own. This article shows you the ones I own in 3 price ranges! This next link takes you to my automotive scan tool reviews.

You have more than likely seen and heard ads for places that will scan your car for free. Before for you go for this service read my article on how much it may cost for free check engine light diagnosis.

With the soft economy people want inexpensive scan tools. But do these things work? I reviewed a laptop usb unit and a hand held on my page about cheap auto scan tools.

When that annoying check light comes on you may want to by-pass it. Learn about why you should not try disconnecting check engine lights.

What's the difference between OBD 2 and the OBD1 diagnostic systems. This article has the details of the major differences of OBD2 VS OBD 1.

Some more in depth information on how the car computer reads the diagnostic information and why the check engine light comes on.

I really do not approve of the idiot light set up on striped model cars. Here is why and how to replace your idiot light with full gauges.

Are you ready to turn out the service engine soon light. Good! here is some information on the DIY reset check engine light procedure.

Fixing your engine light may include learning about the data stream. This article provides tips for reading scan tool data.

Sometimes car mechanics will replace the part if a code sets for it. This can be a costly way to diagnose your failure. Learn how to confirm a failed throttle position sensor.

Computer sensors that produce their own voltages are discussed on this next page. These include the mighty speed sensor as well as other important automotive computer sensors.

One of the common codes to set in a PCM is the o2 fault. Here is an article about the automotive scan tool and oxygen sensor codes.

Okay your ABS light is on and you want to tackle some do it yourself diagnosis. You better read this ABS scan tool article.

Another troublesome red flashing light is the airbag warning indicator. Many failures can make this thing go on but here is one of the most common issues that turn on the air bag light .

Learn more about interesting automotive subjects and view a list of covered material on the about us page.