Dorman 599-102 Transfer Case Control Module

Dorman 599-102 Transfer Case Control Module

Restore transfer case control operation with this Dorman replacement module for vehicles equipped with the NP8 2-speed push-button shift transfer case. Built to match the original module’s function and performance, Dorman 599-102 offers a cost-effective solution when the factory transfer case control module is no longer responding correctly.

Key Features

• Direct replacement transfer case control module for NP8-equipped applications
• Orange connector color for proper vehicle-side identification
• Pin terminal type for OE-style electrical connection
• Replacement for the original transfer case control module function and performance
• Package contents: transfer case control module

Vehicle Fitment

• Fits 2003-2005 Chevrolet Blazer, N/A, with RPO Code NP8 for 2 Speed Push Button Shift Transfer Case.
• Fits 1999-2005 GMC Jimmy, N/A, with RPO Code NP8 for 2 Speed Push Button Shift Transfer Case.
• Fits 1999-2004 Chevrolet S10, N/A, with RPO Code NP8 for 2 Speed Push Button Shift Transfer Case.
• Fits 1999-2004 GMC Sonoma, N/A, with RPO Code NP8 for 2 Speed Push Button Shift Transfer Case.
• Fits 1999-2002 Chevrolet Blazer, N/A, with RPO Code NP8 (2 Speed, Push Button Shift, Transfer Case); Four Button Selection Switch.

Detailed Description

This Dorman transfer case control module is engineered for specific Chevrolet and GMC trucks and SUVs that use the NP8 two-speed push-button shift transfer case. If the original module is failing to command 4WD engagement, range changes, or transfer case communication, Dorman 599-102 provides a direct replacement path for restoring normal system operation. This part cross-references Cardone Reman 73-42102 for the same application.

Compatible With Chevrolet Blazer, GMC Jimmy, Chevrolet S10, and GMC Sonoma applications listed above, this module is a practical OE-style replacement for diagnosing and correcting electronic transfer case control issues. The orange connector and pin terminals help support proper fitment and electrical connection during replacement.

Common Issues This Part May Solve

• Inoperative push-button 4WD selection
• Transfer case not shifting between ranges
• Intermittent or lost transfer case control communication
• Faulty original module causing incorrect transfer case behavior
• Need for a replacement module after electrical failure

Installation Notes and Tips

Verify the vehicle’s RPO code NP8 and connector style before installation. Confirm the application matches the listed Chevrolet Blazer, GMC Jimmy, Chevrolet S10, or GMC Sonoma fitment, including the four-button selection switch note where applicable. Inspect related wiring, connectors, and transfer case components during replacement to help isolate the root cause of the concern.

Quality Assurance

Dorman manufactures replacement parts that mirror the function and performance of original components on specific vehicles. Part number 599-102 is built as a direct-fit transfer case control module for the listed applications.