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Dorman 645-939 Engine Coolant Temperature Sensor Connector
Engine Coolant Temperature Sensor Connector for GM Applications
Dorman 645-939 is an engine coolant temperature sensor connector built to match the original connector’s appearance and function on specified vehicles. It uses quality materials for dependable electrical contact and long-term durability in demanding underhood conditions.
With a 17.1 in. wiring harness length, 18-gauge wire, a female blade terminal, and tin brass terminal material, this connector is built for a direct-style repair on GM trucks, vans, and SUVs. It is a practical replacement for a damaged, heat-affected, or corroded coolant temperature sensor connector.
Key Features
- Engine coolant temperature sensor connector for specified Chevrolet, GMC, and Pontiac applications
- 17.1 in. wiring harness length for serviceable routing
- 18-gauge wire with a single-wire design
- Female blade terminal with tin brass (tin plate) construction
- Built to match original hardware appearance and function
- Cross-references Standard Ignition S-963 and MOOG Driveline Products 838 for the same application
Detailed Description
Dorman 645-939 is designed for vehicles that use a one-wire engine coolant temperature sensor connector, including many Chevrolet Astro, GMC Safari, Chevrolet Express, GMC Savana, and related GM platforms. It also covers select applications such as 1997 Chevrolet Camaro and 1993-1997 Pontiac Firebird, along with numerous C/K-series trucks, vans, and utility models. If you are searching for a coolant temperature sensor connector for a 1992-1995 Chevrolet C1500, 1993-1995 GMC Safari, or 1996-2002 Chevrolet Express 2500, this part number is built for those listed applications.
The connector is engineered to restore a secure electrical connection at the engine coolant temperature sensor, helping maintain accurate signal transfer between the sensor and the vehicle harness. Dorman 645-939 is a direct-fit style repair part for GM cooling-system electrical service, and the part number 645-939 is commonly referenced when replacing a worn connector on Chevrolet and GMC platforms.
What It Helps Fix
- Broken or brittle coolant temperature sensor connector housing
- Corrosion at the terminal connection
- Intermittent temperature signal caused by poor electrical contact
- Heat-damaged wiring near the sensor
- Check engine concerns related to coolant temperature sensor circuit faults
Installation Notes and Tips
Verify the vehicle’s connector style, wire count, and terminal configuration before installation. This part uses a female blade terminal and a single-wire layout, so it should be matched to the original sensor connector on the vehicle. Confirm fitment for your exact year, make, and model, especially on GM trucks, vans, and SUVs with application-specific notes such as heavy-duty heater or manual air conditioning configurations.
For best results, inspect the sensor pigtail area for heat damage, corrosion, or brittle insulation before splicing in the new connector. Use proper electrical repair practices to maintain a solid connection and protect the cooling-system signal circuit.
Quality Assurance
Dorman designs this engine coolant temperature sensor connector to match original hardware function and appearance on listed applications. Quality materials and tin-plated brass terminals support reliable electrical performance in underhood service conditions.
| Brand | Dorman |
|---|---|
| Part Number | 645-939 |
| Wiring Harness Length | 17.1 |
| Wire Gauge Measurement | 18 |
| Terminal Type | Blade |
| Package Contents | 1 harness - 1 butt connector |
| Terminal Gender | Female |
| Terminal Material | Tin brass (tin plate) |
| Wire Quantity | 1 |
This part fits 197 vehicles. Search below:
| Year | Make | Model | # Doors | Transmission | Liters | Cylinders | Position | Notes |
|---|---|---|---|---|---|---|---|---|
| 2005 | Chevrolet | Astro | N/A | |||||
| 2005 | GMC | Safari | N/A | |||||
| 2004 | Chevrolet | Astro | N/A | |||||
| 2004 | GMC | Safari | N/A | |||||
| 2003 | Chevrolet | Astro | N/A | |||||
| 2003 | GMC | Safari | N/A | |||||
| 2002 | Chevrolet | Astro | N/A | |||||
| 2002 | Chevrolet | Express 1500 | 4.3L | V6 | N/A | |||
| 2002 | Chevrolet | Express 1500 | 5.7L | V8 | N/A | |||
| 2002 | Chevrolet | Express 1500 | 5.0L | V8 | N/A | |||
| 2002 | Chevrolet | Express 2500 | 4.3L | V6 | N/A | |||
| 2002 | Chevrolet | Express 2500 | 5.7L | V8 | N/A | |||
| 2002 | Chevrolet | Express 2500 | 5.0L | V8 | N/A | |||
| 2002 | Chevrolet | Express 3500 | 5.7L | V8 | N/A | |||
| 2002 | GMC | Safari | N/A | |||||
| 2002 | GMC | Savana 1500 | 4.3L | V6 | N/A | |||
| 2002 | GMC | Savana 1500 | 5.7L | V8 | N/A | |||
| 2002 | GMC | Savana 1500 | 5.0L | V8 | N/A | |||
| 2002 | GMC | Savana 2500 | 4.3L | V6 | N/A | |||
| 2002 | GMC | Savana 2500 | 5.7L | V8 | N/A | |||
| 2002 | GMC | Savana 2500 | 5.0L | V8 | N/A | |||
| 2002 | GMC | Savana 3500 | 5.7L | V8 | N/A | |||
| 2001 | Chevrolet | Astro | N/A | |||||
| 2001 | Chevrolet | Express 1500 | N/A | |||||
| 2001 | Chevrolet | Express 2500 | N/A | |||||
| 2001 | Chevrolet | Express 3500 | N/A | |||||
| 2001 | GMC | Safari | N/A | |||||
| 2001 | GMC | Savana 1500 | N/A | |||||
| 2001 | GMC | Savana 2500 | N/A | |||||
| 2001 | GMC | Savana 3500 | N/A | |||||
| 2000 | Chevrolet | Astro | N/A | |||||
| 2000 | Chevrolet | Express 1500 | N/A | |||||
| 2000 | Chevrolet | Express 2500 | N/A | |||||
| 2000 | Chevrolet | Express 3500 | N/A | |||||
| 2000 | GMC | Safari | N/A | |||||
| 2000 | GMC | Savana 1500 | N/A | |||||
| 2000 | GMC | Savana 2500 | N/A | |||||
| 2000 | GMC | Savana 3500 | N/A | |||||
| 1999 | Chevrolet | Astro | N/A | |||||
| 1999 | Chevrolet | Express 1500 | N/A | |||||
| 1999 | Chevrolet | Express 2500 | N/A | |||||
| 1999 | Chevrolet | Express 3500 | N/A | |||||
| 1999 | Chevrolet | P30 | N/A | |||||
| 1999 | GMC | P3500 | N/A | |||||
| 1999 | GMC | Safari | N/A | |||||
| 1999 | GMC | Savana 1500 | N/A | |||||
| 1999 | GMC | Savana 2500 | N/A | |||||
| 1999 | GMC | Savana 3500 | N/A | |||||
| 1998 | Chevrolet | Astro | N/A | |||||
| 1998 | Chevrolet | Express 1500 | N/A | |||||
| 1998 | Chevrolet | Express 2500 | N/A | |||||
| 1998 | Chevrolet | Express 3500 | N/A | |||||
| 1998 | Chevrolet | P30 | N/A | |||||
| 1998 | GMC | P3500 | N/A | |||||
| 1998 | GMC | Safari | N/A | |||||
| 1998 | GMC | Savana 1500 | N/A | |||||
| 1998 | GMC | Savana 2500 | N/A | |||||
| 1998 | GMC | Savana 3500 | N/A | |||||
| 1997 | Chevrolet | Astro | N/A | |||||
| 1997 | Chevrolet | Camaro | 5.7L | V8 | N/A | Blue; 1 Wire | ||
| 1997 | Chevrolet | Express 1500 | N/A | |||||
| 1997 | Chevrolet | Express 2500 | N/A | |||||
| 1997 | Chevrolet | Express 3500 | N/A | |||||
| 1997 | Chevrolet | P30 | N/A | |||||
| 1997 | GMC | P3500 | N/A | |||||
| 1997 | GMC | Safari | N/A | |||||
| 1997 | GMC | Savana 1500 | N/A | |||||
| 1997 | GMC | Savana 2500 | N/A | |||||
| 1997 | GMC | Savana 3500 | N/A | |||||
| 1997 | Pontiac | Firebird | 5.7L | V8 | N/A | Blue; 1 Wire | ||
| 1996 | Chevrolet | Astro | N/A | |||||
| 1996 | Chevrolet | Express 1500 | N/A | |||||
| 1996 | Chevrolet | Express 2500 | N/A | |||||
| 1996 | Chevrolet | Express 3500 | N/A | |||||
| 1996 | Chevrolet | P30 | N/A | |||||
| 1996 | GMC | G3500 | N/A | |||||
| 1996 | GMC | P3500 | N/A | |||||
| 1996 | GMC | Safari | N/A | |||||
| 1996 | GMC | Savana 1500 | N/A | |||||
| 1996 | GMC | Savana 2500 | N/A | |||||
| 1996 | GMC | Savana 3500 | N/A | |||||
| 1996 | Pontiac | Firebird | 5.7L | V8 | N/A | Blue; 1 Wire | ||
| 1995 | Chevrolet | Astro | N/A | Connector | ||||
| 1995 | Chevrolet | C1500 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Chevrolet | C1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Chevrolet | C2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1995 | Chevrolet | C35 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Chevrolet | C3500 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Chevrolet | G10 | N/A | |||||
| 1995 | Chevrolet | G20 | N/A | |||||
| 1995 | Chevrolet | K1500 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Chevrolet | K1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Chevrolet | K2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1995 | Chevrolet | K3500 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Chevrolet | P30 | N/A | |||||
| 1995 | Chevrolet | Silverado | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Chevrolet | Suburban 1500 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Chevrolet | Tahoe | Automatic | 5.7L | V8 | N/A | ||
| 1995 | GMC | C1500 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | GMC | C1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1995 | GMC | C2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1995 | GMC | C3500 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | GMC | G1500 | N/A | |||||
| 1995 | GMC | G2500 | N/A | |||||
| 1995 | GMC | G3500 | N/A | |||||
| 1995 | GMC | K1500 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | GMC | K1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1995 | GMC | K2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1995 | GMC | K3500 | Automatic | 5.7L | V8 | N/A | ||
| 1995 | GMC | P3500 | N/A | |||||
| 1995 | GMC | Safari | N/A | w/Heavy Duty Heater | ||||
| 1995 | GMC | Yukon | Automatic | 5.7L | V8 | N/A | ||
| 1995 | Pontiac | Firebird | 3.4L | V6 | N/A | Blue; 1 Wire | ||
| 1995 | Pontiac | Firebird | 5.7L | V8 | N/A | Blue; 1 Wire | ||
| 1994 | Chevrolet | Astro | N/A | Connector | ||||
| 1994 | Chevrolet | Blazer | Automatic | 5.7L | V8 | N/A | ||
| 1994 | Chevrolet | C1500 | Automatic | 5.7L | V8 | N/A | ||
| 1994 | Chevrolet | C1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1994 | Chevrolet | C2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1994 | Chevrolet | G10 | N/A | |||||
| 1994 | Chevrolet | G20 | N/A | |||||
| 1994 | Chevrolet | K1500 | Automatic | 5.7L | V8 | N/A | ||
| 1994 | Chevrolet | K1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1994 | Chevrolet | K2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1994 | Chevrolet | P30 | N/A | |||||
| 1994 | Chevrolet | S10 | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1994 | Chevrolet | S10 Blazer | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1994 | GMC | C1500 | Automatic | 5.7L | V8 | N/A | ||
| 1994 | GMC | C1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1994 | GMC | C2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1994 | GMC | G1500 | N/A | |||||
| 1994 | GMC | G2500 | N/A | |||||
| 1994 | GMC | G3500 | N/A | |||||
| 1994 | GMC | Jimmy | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1994 | GMC | K1500 | Automatic | 5.7L | V8 | N/A | ||
| 1994 | GMC | K1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1994 | GMC | K2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1994 | GMC | P3500 | N/A | |||||
| 1994 | GMC | Safari | N/A | w/Heavy Duty Heater | ||||
| 1994 | GMC | Sonoma | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1994 | GMC | Yukon | Automatic | 5.7L | V8 | N/A | ||
| 1994 | Oldsmobile | Bravada | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1994 | Pontiac | Firebird | 3.4L | V6 | N/A | Blue; 1 Wire | ||
| 1994 | Pontiac | Firebird | 5.7L | V8 | N/A | Blue; 1 Wire | ||
| 1993 | Chevrolet | Astro | N/A | Connector | ||||
| 1993 | Chevrolet | Blazer | Automatic | 5.7L | V8 | N/A | ||
| 1993 | Chevrolet | C1500 | Automatic | 7.4L | V8 | N/A | ||
| 1993 | Chevrolet | C1500 | Automatic | 5.7L | V8 | N/A | ||
| 1993 | Chevrolet | C1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1993 | Chevrolet | C2500 Suburban | 4 Door | Automatic | 7.4L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1993 | Chevrolet | C2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1993 | Chevrolet | G10 | 5.7L | V8 | N/A | |||
| 1993 | Chevrolet | G10 | 5.0L | V8 | N/A | |||
| 1993 | Chevrolet | G20 | 5.7L | V8 | N/A | |||
| 1993 | Chevrolet | G20 | 5.0L | V8 | N/A | |||
| 1993 | Chevrolet | K1500 | Automatic | 5.7L | V8 | N/A | ||
| 1993 | Chevrolet | K1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1993 | Chevrolet | K2500 Suburban | 4 Door | Automatic | 7.4L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1993 | Chevrolet | K2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1993 | Chevrolet | P30 | N/A | |||||
| 1993 | Chevrolet | S10 | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1993 | Chevrolet | S10 | 2.8L | V6 | N/A | w/Heavy Duty Heater | ||
| 1993 | Chevrolet | S10 Blazer | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1993 | GMC | C1500 | Automatic | 5.7L | V8 | N/A | ||
| 1993 | GMC | C1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1993 | GMC | C2500 Suburban | 4 Door | Automatic | 7.4L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1993 | GMC | C2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1993 | GMC | G3500 | 6.2L | V8 | N/A | |||
| 1993 | GMC | G3500 | 7.4L | V8 | N/A | |||
| 1993 | GMC | G3500 | 5.7L | V8 | N/A | |||
| 1993 | GMC | Jimmy | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1993 | GMC | K1500 | Automatic | 5.7L | V8 | N/A | ||
| 1993 | GMC | K1500 Suburban | Automatic | 5.7L | V8 | N/A | ||
| 1993 | GMC | K2500 Suburban | 4 Door | Automatic | 7.4L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1993 | GMC | K2500 Suburban | 4 Door | Automatic | 5.7L | V8 | N/A | w/Manual Air Conditioning Controls; wo/Rear Auxiliary Air Conditioning; w/Radiator Booster Fan |
| 1993 | GMC | P3500 | N/A | |||||
| 1993 | GMC | Safari | N/A | w/Heavy Duty Heater | ||||
| 1993 | GMC | Sonoma | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1993 | GMC | Sonoma | 2.8L | V6 | N/A | w/Heavy Duty Heater | ||
| 1993 | GMC | Yukon | Automatic | 5.7L | V8 | N/A | ||
| 1993 | Oldsmobile | Bravada | 4.3L | V6 | N/A | w/Heavy Duty Heater | ||
| 1993 | Pontiac | Firebird | 3.4L | V6 | N/A | Blue; 1 Wire | ||
| 1993 | Pontiac | Firebird | 5.7L | V8 | N/A | Blue; 1 Wire | ||
| 1992 | Chevrolet | Blazer | 5.7L | V8 | N/A | |||
| 1992 | Chevrolet | C1500 | 5.7L | V8 | N/A | |||
| 1992 | Chevrolet | C1500 | 5.0L | V8 | N/A | |||
| 1992 | Chevrolet | C1500 Suburban | 5.7L | V8 | N/A | |||
| 1992 | Chevrolet | K1500 | 5.7L | V8 | N/A | |||
| 1992 | Chevrolet | K1500 | 5.0L | V8 | N/A | |||
| 1992 | Chevrolet | K1500 Suburban | 5.7L | V8 | N/A | |||
| 1992 | GMC | C1500 | 5.7L | V8 | N/A | |||
| 1992 | GMC | C1500 | 5.0L | V8 | N/A | |||
| 1992 | GMC | C1500 Suburban | 5.7L | V8 | N/A | |||
| 1992 | GMC | Jimmy | N/A | w/Heavy Duty Heater | ||||
| 1992 | GMC | Sonoma | N/A | w/Heavy Duty Heater | ||||
| 1992 | GMC | Yukon | 5.7L | V8 | N/A | |||
| 1992 | Oldsmobile | Bravada | N/A | w/Heavy Duty Heater |
* 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.