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The Best Auto Diagnostic Tool: OBD II Code Scanner


After an expensive visit to my local mechanic, I decided to start investigating my car troubles on my own before needlessly spending money.


Find Out What Your Check Engine Light Means

Have you experienced the dreaded check engine light on your dashboard? It is something we all come across at some point in our driving career, and most of the time, it is just a harmless warning. A simple tool can diagnose it and save us expensive repair bills at the dealer.


A Useful Tool

I have owned many cars in my life. Most of the time, they are great and I drive them to the ground. Most well-made cars do not need much maintenance. Typically, oil change, tires and brakes and mufflers are the most common repairs and maintenance. Rarely, a check engine light comes on and you are instructed to bring it to your dealer for diagnostics. It can be an expensive proposition.

That is what happened to my Toyota Sienna minivan. I had owned it since 2008 with over 160,000 miles. All was well until one day, the check engine light came on. I took it to my local car mechanic and he hooked it up to a diagnostic tool and after a few minutes told me it needed an oxygen sensor. I didn't have much time that day and told him I would bring it back for the repair. The problem was not serious and only caused a drop in the fuel efficiency.

This got me thinking. What is this tool that he used? I looked around and searched on the web and found this product. It was listed for $35 but I was able to find the exact one on Amazon for $22. I ordered it and it arrived in two days. I followed the instructions and it gave me the exact code in a few minutes. I looked it up on the booklet and sure enough, the booklet said it was a sensor that was defective. Then it gave me the option to erase the code. This turned off the check engine light.

NB: The light returned after about 10 minutes of running. It will remain off when the repair is made.

The one I recommend is the Performance Tool W2977 diagnostic scan tool OBDII. It works with most 1996 and later model cars.


This simple tool is a money saver. It can erase the check engine light and save on costly repairs. This will allow my old car to pass annual inspections. It is something every driver should own.

Postscript - Jan. 30, 2020

My 2005 Madza 3 with 153,000 miles just came up with a check engine light. I hooked it up to the OBD II, and the code came out to be P0126. It told me it was related to the coolant temperature. I put some antifreeze and reset the light. Now, it is driving fine and the check engine light stayed off.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

© 2017 Jack Lee


Kingbolen auto scanner center on July 03, 2019:

Thanks for sharing!

MS309 is a old model,Launch Creader 3001 is not bad for you.

New DIY tool CRP129E include 5 reset service.

Tanya on September 24, 2017:

Hi! My name is Tanya, and I am the sale manager at TOPDON. We specialize in professional car OBD diagnose tools. I am reaching out to you on the possibility of getting either an editorial or a video review for our featured OBD2/EOBD Topdon plus Auto Code Scanner.

This product checks engine error codes with O2 Sensor Test, Views Freeze Frame Data, Reads and Clears DTC. It has extensive coverage (works on most 1996 and newer OBD II & CAN domestic or import vehicles) and simple manipulation (One click I/M readiness for a quick check), reads hard (memory) / pending (intermittent), historic codes, and show definitions. Besides, it has exclusive OBD II diagnostics, efficient monitoring and supports multiple languages. Please find more details of the product here: https://www.amazon.com/dp/B01M8MMBLK.

If you are interested in reviewing our latest Topdon Plus, please let me know and I will send out a free sample for you to review.

Thank you for your time and I look forward to hearing back from you.

Best Regards,

Tanya (tanyuxiang000@gmail.com)

Pam Morris from Atlanta Georgia on May 17, 2017:

I enjoyed reading your article. It's very informative, thank you for sharing it.