What do I do now, I have a Check Engine Light
01-16-2015, 05:55 PM
#1
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Join Date: 01-23-2009
Location: Fredericksburg, Virginia
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What do I do now, I have a Check Engine Light
How to research OBD2 codes
Okay you had a "Check Engine Light", somebody told you to go to Advance Auto or O'Reilly's or some other auto parts store to get the codes read. What do you do after you get the code NUMBER?
Do not listen to the sales clerk after they give you the number. You don't even want to hear the name or description of the code! Just the NUMBER, it will probably start with a P and they usually say "O" instead of "0". The only letter involved will be the leading one all engine codes start with a "P" the xxxx. Write it or them down. (some codes will have a letter far the last digit; the codes are actually a scientific notation octal I think)
First: put the number into Google, then follow a few of the links presented. This will give you a feeling for what is going on.
Second: put the number into the ChevyHHR.net search box, then follow a few links.
Third: If you have gotten yourself a bit educated about what is going on and want to know exactly what the codes mean. Go to :https://gsitlc.ext.gm.com/gmspo/mode6/index.html. The information contained on this site can be dangerous if you don't understand the systems involved. It is one of those "too much information" things, but explains exactly what the computer is doing.
(you want to look at the GM CAN - GM Powertrain section under Mode 6 Data, and your year under Engine/Transmission, then look at the "Engine & Transmission Diagnostic Parameter File Matrix" to find which PDF file applies to your car.)
Okay you had a "Check Engine Light", somebody told you to go to Advance Auto or O'Reilly's or some other auto parts store to get the codes read. What do you do after you get the code NUMBER?
Do not listen to the sales clerk after they give you the number. You don't even want to hear the name or description of the code! Just the NUMBER, it will probably start with a P and they usually say "O" instead of "0". The only letter involved will be the leading one all engine codes start with a "P" the xxxx. Write it or them down. (some codes will have a letter far the last digit; the codes are actually a scientific notation octal I think)
First: put the number into Google, then follow a few of the links presented. This will give you a feeling for what is going on.
Second: put the number into the ChevyHHR.net search box, then follow a few links.
Third: If you have gotten yourself a bit educated about what is going on and want to know exactly what the codes mean. Go to :https://gsitlc.ext.gm.com/gmspo/mode6/index.html. The information contained on this site can be dangerous if you don't understand the systems involved. It is one of those "too much information" things, but explains exactly what the computer is doing.
(you want to look at the GM CAN - GM Powertrain section under Mode 6 Data, and your year under Engine/Transmission, then look at the "Engine & Transmission Diagnostic Parameter File Matrix" to find which PDF file applies to your car.)
Last edited by donbrew; 03-31-2022 at 07:52 AM.
07-12-2018, 08:07 AM
#10
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Join Date: 01-23-2009
Location: Fredericksburg, Virginia
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