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My Check Engine Light Is On - What Happens Next?

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  1. step : Reading Diagnostic Codes (0:16)
    • Connect the scan tool connector to the plug under the dashboard
    • Plug the connector into the scan tool
    • Set the scan tool to Global
    • Set the scan tool to your make and model year
    • Turn off the vehicle for ten seconds
    • Turn the key to the on position
    • Open the diagnostic codes menu
    • Choose the read codes option
    • Note the saved codes and their description
  2. step : Clearing a Code (4:42)
    • After repairing the problem, you can clear the code
    • Attach the scanner as in Step 1
    • Go to the diagnostic codes menu
    • Choose the erase codes option
    • Click yes to erase codes
    • Start the vehicle
    • Check that the check engine light is off
    • Drive the vehicle to make sure the check engine light stays off

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Hi, I'm Mike from 1A Auto. I hope this how-to video helps you out, and next time you need parts for your vehicle, think of Thanks.

So, you're cruising in your vehicle and you get a check engine light as you can see here on this vehicle. Now what's that mean? Check engine light actually on newer vehicles, is more of a check vehicle light. That light basically comes on. It could be one that says check engine like that or it could be in the shape of an engine as it is on some other vehicles. The computer has detected a malfunction with some part of the vehicle. What you generally do is take it to your dealer or to some other shop. They find out what the code is. How do they do that? Well they use something like this.

This is a code scanner and this is a fairly generic one. They can range in price, this one was probably around 150 dollars. They can range in price from this to up over 1000 dollars for the more sophisticated ones that detect more things, as far as ABS and different things like that. You'll take the scanner and you'll take a plug, and generally what happens is, up underneath here there'll be a plug to your computer. I'm going to use the camera here to find it. Let's see. Here it is, right over here. Let's plug our scanner up there.

Now we'll take the other end and plug it into our handheld. Actually once you plug it in it'll turn on. It starts giving some menus. We're going to do global and it's already on 2003 Subaru. I don't want to erase the data.

It wants me to turn off the key and then turn it on for 10 seconds: one, two, three, four, five, six, seven, eight, nine, ten. Now I want to read the codes. It's linking up to the vehicle. So I have a PO452. So, this gives me the code here, PO452 which is an evap control system, pressure sensor low. That means there is basically a leak in the evaporative control. Then it has another code but it has no definition for that code. This is probably the one we can do something about. A leak in the evaporation control is usually most often is you didn't put your fuel cap on last time you put gas in your vehicle. That's generally the most common thing that causes a code like this. The second most common is that your filler tube has started to rust out. I actually checked both those things, they look okay.

Actually I'll make an admission. I know it was the fuel cap because I took it off and started up the car a couple times. Just to get the car to throw a code so I could do this little demonstration. Now I'm just going to clear that code from the car.

Go back, and erase codes. Are you sure you want to erase the codes? Yes. Okay, now I'm going to start my vehicle up again. As you can see after the car ran for a little while the check engine light shut off. In normal circumstances I'd drive the car around a little bit and make sure it stayed off. Since I know I took the cap off just to throw the code, I'm pretty sure it's not going to come back on. That's pretty much what happens when you get a check engine code on your vehicle. You take it to your shop, they run a scanner on it. Like I said, if you've got a vehicle and you do some of your own work, these scanners can be had for 200 to 250 dollars. They are invaluable. You can help friends out as well.

They run the scanner, they kind of get an idea of what's wrong with the vehicle, then they do some troubleshooting, and fix the problem

We hope this video helps you out. Brought to you by, your source for quality replacement parts and the best service on the Internet. Please feel free to call us toll-free, 888-844-3393. We're the company that's here for you on the Internet and in person.

Tools needed for replacement:

    Diagnostic Tools

  • Scan Tool

OBDII Multilingual Scan Tool

OBD2 Diagnostic Scan Tool

This part replaces:

  • Reference Number W2976

Part Details

  • Language: English, Spanish, German, French, and Dutch
  • Tool Display: Digital Display
  • Diagnostics System: OBD2 (CAN)
  • Power Source: 12V Vehicle Powered
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