Check Engine Light On problems of the 2020 GMC Sierra 1500

- the ground strap corroded and broke apart. Yes, I have the ground cable that failed, if needed for inspection. - yes!!! the truck's steering kept going in and out of manual steering and the engine reduced in speed allowed, and then the engine cut out on me completely - while I was in the middle of a busy road trying to turn onto a side street. Then the engine would not restart. - I had the truck towed on a flat bed to a GMC dealership nearby. They confirmed the issue was that the ground strap failed. They replaced the part at my cost, which fixed the issues. - yes, the dealership inspected and confirmed the issue was the corroded and broken ground strap. - yes, there were many warning messages that started to appear about 3-4 days prior to the complete failure of the electrical system. I started seeing a message about servicing the trailer brake system, and another about servicing the side detection system. Then a service power steering warning and to drive with care. The check engine light was off and on over that time. - I checked the wire connections iunder my vehicle to check for broken wires or corrosion. I did not find any. I then checked if a hard battery reset would work, but it did not. Lastly, I bought a new battery to replace the existing one, even though the existing battery had no issues even when tested under load. That resolved the issue for about 35 minutes that night and then the next morning. After that, the electrical system failed and the truck would not start. At that point I got towed in to the GMC dealership. I had to leave the truck for a weekend, and the dealership did not come up with a loaner, even though I requested one. I got the truck back on Monday afternoon and everything was working fine since then. - over that weekend, I was amazed to find out about the bulletin gm released to cover only some trucks for the issue, but not others! my truck is still not covered, despite the obvious safety issues I experienced!!.

My 2020 5. 3 l GMC at4 is experiencing loss of power with bucking & stalling. Cylinders are not activating when called check engine light is flashing, it starts rough and makes numerous noises at various speeds, as well as at idle. So I brought my vehicle to my local auto repair shop. Our mechanic found two failed fuel injectors and a failed throttle body. Then the loud knocks in my block failed an acoustic test. He also determined the lifters, push rods and camshaft are experiencing excessive wear. The afm system has failed! he warned me that further use of my motor (with only 42k miles on it) will cause a catastrophic failure. My research shows that these issues are becoming common of 5. 3 GMC motors. We searched the country for a rebuilt motor and found that none are available for the next several months. However, I was able to find a new motor at much greater cost. GMC has declined assistance at this time. My vehicle has no value as is, so I ordered the new gm engine. Without the dod system, these engines were designed to go well over 100,000 miles. I am a faithful GMC owner and none of my previous GMC trucks (2003, 2013, 2015, 2019) had such a major problem. Now the 2020's fuel saving system has failed and requires repairs that amount to half the value of my truck. When a full size truck stalls on the highway it's certainly life threatening.

~tl-the contact owns a 2020 GMC Sierra 1500. The contact stated that intermittent the vehicle would not start. The contact also stated that the vehicle failed to start rondonwnly. The contact stated when he start the vehicle using the key fob, the vehicle failed to start but when he attempted a second time using the key fob the vehicle started. The contact stated that the first time when the failure occurred when he try the push button to start the vehicle the vehicle failed to start but with a second attempt after hours with the push button the vehicle started. The contact stated that the failure occurred twiced. The contact stated that the check engine warning light illuminated the first time when the failure first occurred. The contact stated that on his way to the dealer the check engine warning light unilluminated. The vehicle was taken to mckenzie Buick-GMC, 6500 caroline st, milton, FL 32570, and was diagnosed but was not able to find a failure code. However, the failure recurred the contact called the same dealer and informed them of the failure. The vehicle was not yet taken to a dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 86. Aw.