AMCC Diesel Glow Plug Controller Fit Compatible with Chevrolet Silverado 2500/3500 2001-2005, for GMC Sierra 2500/3500 2001-2005, for Cadillac Escalade/Chevrolet Tahoe 2005 Replaces:RY1556&97379635 Fitment: This diesel glow plug controller will fit for Chevrolet Silverado 2500 2001-2005, for Chevrolet Silverado 3500 2004-2005, for GMC Sierra 2500 2001-2004, for GMC Sierra 3500 2004-2005, for Chevrolet Tahoe 2005, for Cadillac Escalade 2005 Replace Part Number: RY-1556&RY1556&97304030&97379635 Premium Materials: The diesel glow plug module controller is crafted with heat-resistant materials to ensure stable performance in high-temperature environments. Its corrosion-resistant casing protects against humidity and harsh conditions, extending its lifespan. High-quality insulating components inside reduce the risk of electrical short circuits, greatly enhancing safety and reliability Function: The diesel glow plug module controller controls preheat time based on ambient temperature and engine status for smooth startup. Whether you're starting your vehicle in cold weather or after a long period of parking, this module provide the necessary support for a reliable ignitions. It maintains optimal temperature to improve combustion efficiency and reduce emissions, with real-time diagnostics and protection to prevent overheating and voltage overload, extending engine life AMCC products are guaranteed for one year after sale，100% inspection and testing prior to shipment