Dorman 599-254 Transfer Case Control Module

Transfer Case Control Module for NP1 Applications

Dorman 599-254 is a replacement transfer case control module for specific Chevrolet Colorado and GMC Canyon trucks equipped with the NP1 2-speed electronic shift transfer case. It restores the original module function on affected vehicles and provides a cost-effective OE-style solution for transfer case control issues.

Key Features

• Direct replacement transfer case control module for select GM trucks
• Built for vehicles with RPO code NP1 and electronic shift transfer case operation
• Black connector with female connector gender and blade terminals
• Metal and plastic housing construction
• Measures 4 in. long and 5.5 in. wide
• Uses 16 and 20 terminal configurations as specified for the application
• Cross-references GM part number 12587044

Detailed Description

This Dorman transfer case control module, part number 599-254, is made for 2004-2012 Chevrolet Colorado and 2004-2012 GMC Canyon models with RPO code NP1. If the original module is no longer controlling the transfer case correctly, this replacement restores the same function and performance expected from the factory unit. It is a practical choice for drivers searching for a 2004-2012 Chevrolet Colorado transfer case control module or a 2004-2012 GMC Canyon electronic shift transfer case module.

The module features a black connector, female connector gender, male terminals, and blade terminal type. Its metal and plastic housing supports the original-style fit and electrical interface needed for proper transfer case operation. Dorman 599-254 is also a direct cross-reference for GM 12587044.

Common Issues This Module Can Address

• Transfer case not shifting between 2WD and 4WD modes correctly
• Electronic shift commands not reaching the transfer case
• Intermittent or failed transfer case control operation
• Loss of proper module communication in NP1-equipped trucks
• Need for an OE-style replacement after module failure

Installation Notes and Tips

Verify the vehicle has RPO code NP1 before ordering. Match the connector style, terminal count, and housing dimensions to the original module before installation. After replacement, confirm transfer case operation through all commanded modes and clear any stored diagnostic trouble codes if required by the vehicle.

Quality Assurance

Dorman supplies replacement components that follow the function and performance of the original part for specific applications. Part number 599-254 is built as a direct-fit replacement for the listed Chevrolet Colorado and GMC Canyon fitments.