Chevrolet and GMC have issued a critical service bulletin for the 2023 models of the Chevrolet Silverado 1500 and GMC Sierra 1500 equipped with the 3.0L Duramax Diesel Engine (LZ0). This bulletin, numbered 23-NA-193 and dated November 2023, is aimed at addressing specific diagnostic trouble codes (DTCs) that have been identified in these models.

TSB 23-NA-193 – Affected Vehicles

This technical service bulletin explicitly targets the 2023 Chevrolet Silverado 1500 and GMC Sierra 1500 models. These vehicles have been sold across various regions including the United States and Canada

2023 GMC Sierra Denali 1500
2023 GMC Sierra Denali 1500

Identified Issue

Owners of the affected vehicles may notice the Malfunction Indicator Lamp (MIL) illuminated on the Driver Information Center (DIC). Technicians diagnosing the issue may find one or more of the following DTCs: P20EE, P22FE, P2C7A, P2EAD, P20FE, P2203, P22FB, P2459, P049D, P0300, and/or P1C30. These codes indicate the presence of software anomalies in the vehicle’s system.

Solution and Service Procedure

The solution proposed in this bulletin is an update to the LZ0 Engine Control Module (ECM). This update is crucial for rectifying the software anomalies causing the DTCs. If you think your vehicle may be affected under this TSB, a visit to your dealer will confirm the issue and, if needed, update your ECM.

2023 Silverado High Country With the 3.0L Duramax Diesel Engine
2023 Silverado High Country With the 3.0L Duramax Diesel Engine (Courtesy Pickup Truck + SUV Talk)

Warranty Information

If your vehicle is still under warranty for emissions, this update will be free of charge. Loaner vehicles may be available depending on which dealership you visit and how long the service visit will take.

In Conclusion

Owners of the affected 2023 Chevrolet Silverado 1500 and GMC Sierra 1500 models who are experiencing the above-noted errors and check engine light are advised to contact their dealers to schedule the ECM update.