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Dorman 599-101 Transfer Case Control Module
Transfer Case Control Module for NP1 Applications
Restore transfer case operation with this Dorman transfer case control module, Part Number 599-101. It replaces the original module on specific Chevrolet and GMC trucks and SUVs equipped with the 2-speed electronic shift transfer case, helping return proper electronic control and drivability.
- Direct replacement transfer case control module for select NP1-equipped vehicles
- Blue connector color with pin terminal type
- Provides the same function and performance as the original module on listed applications
- Package contents: transfer case control module
- Cross-references OE numbers 73-42101 and 15988924 for the same application
Detailed Product Information
Dorman 599-101 is a replacement transfer case control module for vehicles using the NP1 2-speed electronic shift transfer case. It is built for specific Chevrolet Blazer, Chevrolet S10, GMC Jimmy, and GMC Sonoma applications, giving technicians and owners a cost-effective way to restore electronic transfer case control when the original module is no longer functioning correctly. The blue connector and pin terminal layout support proper electrical connection in the intended vehicle platforms.
Compatible With 1995-1997 Chevrolet Blazer, w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case); 1994-1997 Chevrolet S10, w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case); 1995-1997 GMC Jimmy, w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case); and 1994-1997 GMC Sonoma, w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case). Search terms such as transfer case control module for 1994-1997 Chevrolet S10 NP1 or 1995-1997 GMC Jimmy electronic shift transfer case module apply to this part number 599-101.
Common Problems This Part Can Address
- Transfer case shift commands not responding
- Electronic 4WD or 2-speed transfer case control faults
- Intermittent or failed transfer case module operation
- Loss of proper communication between the switch and transfer case system
- Need for an OE-style replacement for a failed original module
Installation Notes and Quality Assurance
Verify the vehicle RPO code NP1 and connector style before installation to confirm application match. Inspect the harness, terminals, and related transfer case components for damage or corrosion before replacing the module. Dorman is known for replacement parts that mirror original function on specific vehicle applications, and this module is intended to restore the factory electronic transfer case control strategy on the listed Chevrolet and GMC models.
| Brand | Dorman |
|---|---|
| Part Number | 599-101 |
| Connector Color | Blue |
| Package Contents | Transfer Case Control Module |
| Terminal Type | Pin |
This part fits 14 vehicles. Search below:
| Year | Make | Model | Drive Type | Position | Notes |
|---|---|---|---|---|---|
| 1997 | Chevrolet | Blazer | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1997 | Chevrolet | S10 | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1997 | GMC | Jimmy | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1997 | GMC | Sonoma | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1996 | Chevrolet | Blazer | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1996 | Chevrolet | S10 | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1996 | GMC | Jimmy | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1996 | GMC | Sonoma | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1995 | Chevrolet | Blazer | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1995 | Chevrolet | S10 | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1995 | GMC | Jimmy | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1995 | GMC | Sonoma | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1994 | Chevrolet | S10 | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
| 1994 | GMC | Sonoma | 4WD | N/A | w/RPO Code NP1 (2 Speed, Electronic Shift, Transfer Case) |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.