NHTSA Complaint #11698575 — 2020 GMC SIERRA 1500
ELECTRICAL SYSTEM issue reported to NHTSA
Complaint Details
| ODI Number | 11698575 |
| Vehicle | 2020 GMC SIERRA 1500 |
| Component | ELECTRICAL SYSTEM |
| Date of Incident | |
| Date Filed | |
| Mileage | N/A miles |
| Crash | No |
| Fire | No |
| Injuries | 0 |
| Deaths | 0 |
| Vehicle Towed | No |
| State | MI |
Consumer Description
1. The vehicle’s emissions system is malfunctioning, specifically the ECM (Engine Control Module) related to the exhaust emissions system. The diagnostic trouble code is P2C7A, indicating the system is not performing as expected. Key components such as the NOx catalytic converters and diesel particulate filter have been repeatedly replaced, but the issue persists. The vehicle and all replaced components are available for inspection upon request. 2. The malfunctioning emissions system has led to an exhaust leak that allowed exhaust gases to enter the vehicle’s cab. This creates a hazardous environment for both the driver and passengers, exposing them to harmful exhaust fumes. In addition to reduced engine performance, poorer fuel economy, and emissions non-compliance, this exhaust leak poses a serious safety risk by compromising the air quality inside the vehicle. Prolonged operation under these conditions could lead to adverse health effects and further mechanical failures that impact vehicle safety. 3. Yes. The dealership has diagnosed the problem multiple times. The emissions components have been replaced under warranty on two separate occasions. The dealer attributed the fault to fuel quality; however, Fuel distributor debunked these claims. 4. The vehicle has been inspected extensively by the dealership with invoiced repair work replacing key emissions control components. 5. The check engine light and Service Engine Soon (SES) light have been illuminated with the diagnostic code P2C7A since the initial identification of the problem which started 3JUN24
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