Dorman 599-103 Transfer Case Control Module

Transfer Case Control Module for AWD Applications

Dorman 599-103 is a replacement transfer case control module for specific all-wheel drive vehicles that use the NP4 transfer case system. It restores control module function with the same operating role as the original unit on supported applications, including Buick Rainier, Saab 9-7x, and Oldsmobile Bravada.

• Replacement transfer case control module for NP4 all-wheel drive transfer case systems
• Black connector color with pin terminal type
• Direct-fit style service part for selected GM-platform AWD vehicles
• Paraphrases OE function for cost-effective module replacement
• Part number 599-103 for easy identification

Detailed Product Overview

This Dorman transfer case control module is built for vehicles where the original module is no longer managing transfer case operation correctly. It serves the same function as the factory unit on specific applications and is intended for use on 2002-2004 Oldsmobile Bravada w/RPO Code NP4, 2004-2005 Buick Rainier w/RPO Code NP4, and 2005 Saab 9-7x w/RPO Code NP4. If you are searching for a transfer case control module for a 2004 Buick Rainier NP4 AWD system or a 2005 Saab 9-7x transfer case control module, this part number 599-103 is the relevant replacement to review.

This part cross-references GM OE 12590220 for the same application.

What It Helps Resolve

• Transfer case control module communication faults
• Loss of electronic control over AWD transfer case operation
• Erratic or inconsistent transfer case engagement
• Module-related drivability issues tied to NP4 system control
• Replacement needs after the original control module fails

Installation Notes and Tips

Verify the vehicle’s RPO code NP4 before ordering. Confirm connector style and terminal type match the original module, and compare the existing part number to 599-103 and 12590220 for application confirmation. Installation should be performed with the vehicle’s electrical system properly diagnosed so the replacement module addresses the root cause of the transfer case control issue.

Quality Assurance

Dorman supplies this module as a replacement part that matches the original unit’s function and performance on listed vehicles. It is intended as a practical OE-style service solution for NP4-equipped Buick Rainier, Saab 9-7x, and Oldsmobile Bravada models.