Cadillac Check Engine Light Stays On
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Is your Cadillac Check Engine Light ON or Flashing? Learn how to read the codes and discover why your Cadillac check engine light comes on.
There are over 500 different fault codes that can trigger the check engine light on a Cadillac. You will need to read codes to find out why the check engine light on your Cadillac is on.
Symptoms
Symptoms of a check engine light can vary depending on the fault code that triggered the light. Possible symptoms include:- Poor throttle response
- A decrease in fuel economy
- Engine misfire
- Difficult to accelerate or go uphill
- Engine shakes or excessive vibrations
- The car won’t stay running.
Common Causes
Cadillac check engine light can turn on for various reasons, including something as simple as a loose gas cap.- Loose gas cap
- Faulty MAF sensor
- Oxygen sensor
- Catalytic converter
- EVAP leak
- Vacuum leak
- EGR Valve
How to read Cadillac codes
The following steps provide information on how to read Cadillac fault codes from the Engine Control Unit (ECU).What you will need
The YOUCANIC UCAN-II Pro reads Cadillac engine codes, including manufacturer specific ones, and shows freeze frame data, which tells you the speed, temperature and load when the fault set.
Video
Procedure
- Locate the OBD-2 port under the dashboard of your Cadillac on the driver’s side. This is a 16-pin port, and all 1996 and newer Cadillac vehicles have this port.
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Connect Scanner. Plug your scanner or Bluetooth adapter into the OBD2 port.
At a Glance
- On Cadillacs with the 3.6 V6, codes such as P0008, P0016 or P0017 often point to a stretched timing chain.
- Low or old oil speeds up timing chain wear, so check the oil level first.
- A flashing light means a misfire; reduce speed and get it checked right away.
- Read the code and freeze frame before replacing parts.
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Turn the ignition ON, key in position II. All Cadillac dashboard lights will turn on but do not start the engine. If your Cadillac has a Start/Stop button, you must press the START button without pressing the brakes.
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Turn on the scanner. Allow your OBD2 scanner to turn on and connect to your Cadillac Engine Control Unit (ECU). This step can take up to one minute.
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Read Codes. Read Cadillac check engine light codes from the Engine Control Unit (ECU).
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Clear Codes. Once you have read the codes and fixed the underlying problem, you can return to clear Cadillac CEL codes. Go to the Erase Codes menu. Select YES to clear the Cadillac check engine light.
- Check engine light codes should only be cleared (erased) after fixing the problem that triggered the light.
Reading Cadillac check engine light codes and resetting it once you fix the problem is straightforward. Any Cadillac owner can read and clear the Cadillac check engine light at home.
This procedure works on Cadillac ATS, CTS, XTS, CT6, XT5, Escalade, SRX, DTS, STS, BLS, XLR, and other models.
The YOUCANIC UCAN-II Pro can help you determine the cause of the check engine light in your Cadillac. This powerful scanner can read and clear codes from all the systems present in your vehicle.
OnStar Subscribers
If subscribed to OnStar, press the button to connect to an Advisor. They can run a diagnostic check and retrieve the trouble code(s) from the Engine Control Unit (ECU).
If you are not subscribed to OnStar, follow the instructions to read the fault codes yourself. This procedure is effortless and takes less than five minutes.
I have a 2007 escalade and I have few warning lights on. The scanner pointed me to a couple of the problems but on a couple others it said it cant connect to the ecu. Why is it reading some problems and not others?
2015 Cadillac SRX. I changed my low beam head light bulbs to LED bulbs trying to get more light. Now the check engine light is on. Is this related?
My 2005 Cadillac cts chef engine light came on after my car was shut off and stays on and drains my new battery. What could be causing the issue please help. This is one among a few issues I’ve been having. Really love this car.
O’Reilly will check the codes for free. They have always been helpful.
How much did you Pay at O’Reilly to have your car checked???
Hello my name is Jeanette I have a 2007 Cadillac STS my engine light on I went to O’Reilly to get it checked and they gave me codes I do not understand p0455 p0301 p0300
No the check engine light should not come on because you haven’t changed the oil. Hope this helps.
Can a past due on you’re oil change or due on the date cause check engine light to come on a ats 2014
My car has less then 96k miles and the check engine light came on and it showed codes p0017 & p0008. Gm issues a service bullentin (11340) and later extended it to include the 2009 Cts ( 11340c) for premature timing chain wear. Even though my cars make, model and year is listed under sb 11340c, when you call gm, they say my VIN isn’t included. Obviously, my car which year is listed should be covered and gm should repair under this sb. It is the exact same issue the sb was issued for. Gm is scamming their customers and there needs to be a recall for this issue. I read thousands of people complaining about the same issue, and all that needs to happen is for the htsa to require all the 2009 Cts that had to have this issues repaired at their own expense while gm reaps the rewards of each car that they have a known engineering issue.