Auto Computer Codes, What They Are, and How To Read Them

Eddie Carrara

The OBD2 system was implemented to all new vehicles; it is designed to lower vehicles emissions and make them less intrusive to the environment. 

What is unique about OBD2 is that it is a universal application for all late model vehicles and can be accessed through a universal port called the DLC (Data Link Connector) or OBD2 port (On Board Diagnostics 2 Port) which is usually found under the dash, on the driver's side on most vehicles.  Some vehicles, like Honda, have place them behind the ashtray, but for most vehicles, looking up under the dash where the drivers legs would be positioned, is where you will usually find this connector.

In earlier years, you would have to bring your vehicle to a mechanic or own a OBD scan tool, in order to have the auto computer codes or DTC's pulled from the vehicles ECU (Engine Control Unit).  Now it's as easy as pulling out your Smartphone, iphone, laptop, or tablet and connecting it wirelessly to retrieve the DTC's, yes you would have to buy an App and a Bluetooth adapter  but the cost is minimal compared to what it would cost to have a garage or shop pull the code. Shops usually charge a minimum of 1 hour to pull a code, and that does not include repairing the vehicle.

Benefits to Knowing Diagnostic Trouble Codes

The benefit to having this Bluetooth adapter is that if you have a simple code, like a gas cap code or a misfire code, you can diagnose it where ever you are, clear it, and be on your way. The second benefit, is knowing what the code is, even if you're going to have a garage or shop repairing it for you, you'll have the knowledge of what's wrong with you car before they even look at it, that information is priceless and you can't get taken for a ride!

The average cost of an ELM 327 Bluetooth OBD2 scan tool is $15- $60 depending on you specific application.  If you own an iphone, I recommend buying the iOBD2 for $60 and spending the $4.99 on the App, you're guaranteed not to have any problems with communication or App conflicts.  If you're using a Droid, Samsung, or HTC, it will cost less for the adapter and the Free App will give you all the information you need, there are paid Apps, but unless you want to get techie, there is no need to spend the money.

Buying a ELM 327 Bluetooth OBD2 Code Reader

Before you rush out and buy your auto computer codes reader, I highly recommend researching which scanner is right for your phone. The vehicles diagnostic trouble codes are universal, but the phone adapters are not. I recommend reading customer reviews on the product before making a decision, and I recommend purchasing it from an online retailer with an easy return policy, just in case you have any problems, you don't want to have any hassles if you need to return it.

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Comments (2)
No. 1-2

2006 rav 4. Got new battery. Now the battery light blinks on n off till it gets warm. What’s going on with that. Trying to see if I can get a answer before taking it to Toyota n paying 110.00 just to look at n tell me


2006 rav 4. Engine light. Abs light 4 wh dr light all come on. Says error 500 senors by transmission I just replaced two weeks ago n now it come on. If I shut car off n on blows low beams. If I drive at least 45 min they all go off but I don’t touch the car as far as on n off what can I do