New ECU installed now it will not start

2011 CHEVROLET EQUINOX
116,000 MILES • 2.4L • 4 CYL • 2WD • AUTOMATIC
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KEVIN STINEMATES
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I have had trouble with my ECU so I bought a replacement unit and installed it. when I turn the key all the lights come on but it wont turn over at all and the check engine light is flashing. Is this possibly because of my keys not being set to the new ECU? The company I bought this ECU from had set it to my VIN number do I still have to do the keys?
Dec 14, 2019 at 6:06 PM
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JACOBANDNICKOLAS
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Hi,

The process for key relearning doesn't involve the ECM. What did the manufacturer tell you? Also, was the car's battery disconnected when the new ECM was installed?

Let me know.
Joe
Dec 14, 2019 at 7:34 PM
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KEVIN STINEMATES
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Yes, I disconnected the battery while switching the ECU out. I put the old one back to see if it would work and it did. Do I need to have the new ecu reprogrammed? When I ordered the new ecu I was told this should be a plug and play type of install but when I switched them and turned the key all the normal dash lights came on but it did not do anything else. Just flash the check engine light.
Dec 14, 2019 at 7:42 PM
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JACOBANDNICKOLAS
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I think you got a faulty part. Is there a theft light flashing?
Dec 14, 2019 at 10:32 PM
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KEVIN STINEMATES
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No there isn't a theft light flashing. I did go through the process of trying to see if that might be the problem but it didn’t work either. Thank you for your help. I will have to call the company where I bought the ECU from.
Dec 15, 2019 at 2:38 AM
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JACOBANDNICKOLAS
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Let me know what you find. Based on what you are saying, it sounds like that is the problem.

Take care,
Joe
Dec 15, 2019 at 5:19 PM
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GDZANML
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Did you ever figure this out? I’ve gone through three replacement ECMs, so it’s got to be something else. I’ve done the relearn a bunch of times just in case, to no avail.
Jun 10, 2022 at 9:08 PM
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JACOBANDNICKOLAS
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Hi,

I'm sorry, but he never replied back. Exactly what is happening?

Let me know.

Joe
Jun 11, 2022 at 7:00 PM
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