NHTSA campaign 21V496000 · Manufacturer campaign N212329840
Chevrolet and GMC Recall 21V-496: Short Circuit In Engine Block Heater Cable
NHTSA recall 21V496000 (Manufacturer campaign N212329840) was reported by General Motors, LLC on July 1, 2021, with 338,020 vehicles potentially affected (per NHTSA). NHTSA's record lists the Chevrolet Silverado 2500, Chevrolet Silverado 3500, GMC Sierra 2500 and more for model years 2017–2019. Owners were notified on April 4, 2022, per NHTSA.
Updated daily from NHTSA's recall files
Is my vehicle included?
This page lists, by model year, the vehicles NHTSA's recall record names for campaign 21V496000 in the model years try.vin imports (1995 and later); NHTSA's own record can list more. A model year on the list doesn't mean every vehicle of that year is included, and some may already have been repaired.
To see whether a specific vehicle is included and still needs the repair, enter its VIN at nhtsa.gov/recalls.
Free VIN check: decode a VIN to see its year, make and model.
Key facts
- NHTSA campaign
- 21V496000 (also written 21V-496 or 21V496)
- Filed by
- General Motors, LLC
- Manufacturer campaign number
- N212329840
- Report received
- Potentially affected
- 338,020 vehicles (per NHTSA)
- Component
- Equipment — Electrical — Engine Block Heater
- Owners notified
Repair completion: 80.69% (latest rate the manufacturer reported to NHTSA; dataset updated October 21, 2026)
NHTSA cautions against comparing completion rates across recalls or manufacturers. How try.vin reads them.
Vehicles listed for this recall
NHTSA's recall record lists these vehicles for recall 21V496000. try.vin imports model years 1995 and later, so NHTSA's own list can be longer. Model years with a try.vin recall page link to it. Build dates are NHTSA's range for a model year (per NHTSA); a vehicle built in that range is not necessarily included.
NHTSA's recall notice
As NHTSA's recall record states it for campaign 21V496000.
Defect description
General Motors, LLC (GM) is recalling certain 2017-2019 Chevrolet Silverado 2500, 3500 and 2017-2019 GMC Sierra 2500 and 3500 vehicles equipped with a Duramax diesel 6.6 liter engine and an optional engine-block heater cord. An electrical short-circuit may occur in the engine-block heater cable or in the terminals that connect the heater cable to the block heater.
Safety consequence
An electrical short-circuit can increase the risk of a fire.
Manufacturer remedy
Dealers will replace engine block heaters and heater cords. Vehicles that have this feature disabled as a remedy to the safety condition will be contacted and offered replacement block heaters and heater cords under a separate customer satisfaction program, free of charge. GM will provide free replacement block heaters and cords under a separate customer satisfaction campaign. For vehicles previously included in recall 19V-328, the heater cord will be replaced and rerouted, free of charge. Interim owner notifications were mailed on August 13, 2021. Owner notification letters are expected to be mailed on April 4, 2022. Customers may call GMC customer service at 1-800-462-8782. GM's number for this recall is 212329840.
Notes
Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.
Sources
Official NHTSA notice for recall 21V496000
Campaign details come from NHTSA's recall files, which try.vin imports once a day. The plain-language subject and the completion rate come from the U.S. Department of Transportation's Recalls Data dataset. How try.vin reads recall data.