Dorman 599-108 Transfer Case Control Module

Transfer Case Control Module for NP1 Applications

Dorman 599-108 is a replacement transfer case control module for specific GM trucks and SUVs with the NP1 2-speed electronic shift transfer case. It restores electronic transfer case control with a cost-effective OE-style replacement built to match the original module’s function and performance.

Use this module when the transfer case control system is no longer responding correctly in applications such as the Chevrolet Tahoe, GMC Yukon, and Cadillac Escalade.

Key Features

• Replacement transfer case control module for NP1 electronic shift systems
• White connector color with pin terminal type
• Direct-fit service part for specific GM 4x4 applications
• Designed to provide the same function and performance as the original module
• Package contents: transfer case control module

Detailed Description

Dorman 599-108 is engineered for vehicles equipped with the NP1 2-speed, electronic shift transfer case, including 1997-2000 Chevrolet K1500, K2500, Tahoe, K1500 Suburban, K2500 Suburban, 1997-2000 GMC K1500, K2500, Yukon, K1500 Suburban, K2500 Suburban, and 1999-2000 Cadillac Escalade. This transfer case control module is a practical replacement when the original unit fails to communicate or control transfer case operation properly. This part cross-references Cardone Reman 73-42107 for the same application.

What It Helps Solve

• Loss of electronic 4WD or transfer case shift control
• Intermittent or non-responsive transfer case operation
• Faults related to the transfer case control module
• Replacement needs after module failure in NP1-equipped GM vehicles
• Restoration of transfer case control in Chevrolet Tahoe, GMC Yukon, and Cadillac Escalade applications

Installation Notes and Tips

Verify the vehicle is equipped with RPO code NP1 before ordering. Confirm connector style and terminal type match the original module, and inspect related transfer case wiring, switches, and power/ground circuits during diagnosis. For best results, clear any stored transfer case codes after installation and perform a system relearn or calibration if required by the vehicle.

Quality Assurance

Dorman replacement electronics are built to serve as direct-function alternatives to the original part on the listed applications. Part number 599-108 is intended for specific GM NP1 transfer case systems and is identified by a white connector with pin terminals for proper fitment verification.