Engine derated?

2019 CHEVROLET EQUINOX
48,000 MILES • 1.5L • 4 CYL • 4WD • AUTOMATIC
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DAVENPORT
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Great little car. Zero problems until now. Loaned car to granddaughter. Came back derated. Codes said wheel sensors - replaced. Then Pedal sensor - replaced twice. Then throttle body - replaced. Then still would not communicate with the ECM - replaced. Still doesn’t communicate. Please help!
Jul 8, 2025 at 4:04 PM
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STRAILER
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The ECM will not communicate if you have a fuse out. I would check the ECM and ECM? TCM fuses under the hood and the fuse #6 in the battery fuse panel near the battery (250amp). This guide can show you how:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Also, check the "DLC left" fuse in the fuse panel on the left side of the dash. You might want to go over this video as well:

https://www.youtube.com/watch?v=6Tlg3JmgNSQ

Please go over these guides and get back to us.
Jul 9, 2025 at 6:38 PM
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DAVENPORT
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Thank you, Ken L. We will check the fuses as you have directed and report back. Appreciate your help immensely!
Jul 10, 2025 at 12:45 AM
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STRAILER
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Sounds good :) have a good day!
Jul 10, 2025 at 9:46 AM
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DAVENPORT
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The problem was the electrical harness between the pedal sensor and the ECM. To find it required 2 pedal sensors, throttle body, ECM, and then the harness. I appreciate your reply, as it put the person diagnosing the problem onto the sleuthing it took to discover what was wrong. This was a very difficult repair to find. One wire in miles of electronics. The repair recommended sequence did not point to the harness - this was a rare problem.
Aug 14, 2025 at 9:14 PM
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STRAILER
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Yep, they happen, nice work finding the problem and getting back to us. Please use 2CarPros anytime we are here to help.
Aug 15, 2025 at 12:13 PM