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Standard Ignition S-638 Engine Coolant Temperature Sending Unit Switch ConnectorOE Quality 60-Day Returns
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Part #: S-638

Standard Ignition S-638 Engine Coolant Temperature Sending Unit Switch Connector

⚙️ 200 vehicles fit this part
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🚗Fitment: Buick, Cadillac, Pontiac, Suzuki, Oldsmobile, Dodge, Chevrolet, and GMC, Lucerne, DTS, LaCrosse, Grand Prix, XL-7, DeVille, Bonneville, Regal, Seville, Aurora, Eldorado, Viper, LeSabre, Riviera, 88, LSS, Regency, Park Avenue, 98, Allante, Commercial Chassis, Fleetwood, Metro, Typhoon, Cutlass Cruiser, Toronado, Reatta, Sprint, Tracker, Delta 88, Electra, Nova, Spectrum, and Cutlass Salon
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Overview of Standard Ignition Engine Coolant Temperature Connector

The Standard Ignition S-638 Engine Coolant Temperature Sending Unit Switch Connector is designed for reliable electrical connections in your vehicle's cooling system. This male connector with a pigtail assembly ensures secure and efficient communication between the engine coolant temperature sensor and the vehicle's electrical system.

  • Connector Gender: Male
  • Connector Quantity: 1
  • Includes pigtail assembly for easy installation
  • Terminal Gender: Female
  • Terminal Quantity: 4
  • Terminal Type: 4 blade terminals
  • Wire Quantity: 4 wires included

Detailed Product Description

The Standard Ignition S-638 connector is engineered to maintain a stable and durable connection for the engine coolant temperature sending unit switch. Featuring a male connector with four female blade terminals, this pigtail assembly supports four wires, providing a robust interface for accurate temperature signal transmission. Compatible with a range of vehicles including Buick, Cadillac, Chevrolet, Dodge, GMC, Oldsmobile, Pontiac, and Suzuki models such as the Buick LeSabre, Cadillac DeVille, Chevrolet Camaro, Pontiac Grand Prix, and Suzuki XL-7, this connector meets the specific electrical requirements of these applications.

Common Applications and Issues Addressed

  • Restores proper electrical connection to the engine coolant temperature sensor
  • Eliminates intermittent temperature gauge readings or sensor signal loss
  • Prevents engine overheating caused by faulty sensor connections
  • Resolves check engine light codes related to coolant temperature sensor circuit
  • Replaces damaged or corroded connectors in the cooling system wiring harness

Installation Notes and Tips

  • Ensure the vehicle is turned off and cooled before installation
  • Verify connector orientation: male connector with female terminals
  • Check wire integrity and secure all four wires firmly in the terminals
  • Use dielectric grease to protect terminals from moisture and corrosion
  • Confirm compatibility with your specific make and model before installation

Quality Assurance and Warranty

Standard Ignition parts are manufactured to meet or exceed OEM specifications, ensuring reliable performance and durability. The S-638 connector undergoes rigorous quality control to provide consistent electrical connectivity. While specific warranty details may vary, Standard Ignition typically offers coverage against defects in materials and workmanship. Consult product documentation or your parts provider for exact warranty terms.

BrandStandard Ignition
Part NumberS-638
Connector GenderMale
ContentsPigtail Assembly
Terminal GenderFemale
Terminal Type4 Blade Terminals

This part fits 200 vehicles. Search below:

YearMakeModelLitersCylindersPositionNotes
2011BuickLucerne4.6LV8N/A
2011CadillacDTS4.6LV8N/A
2010BuickLucerne4.6LV8N/A
2010CadillacDTS4.6LV8N/A
2009BuickLaCrosse3.8LV6N/A4 Term. Female
2009BuickLucerne4.6LV8N/A
2009CadillacDTS4.6LV8N/A
2008BuickLaCrosse3.8LV6N/A
2008BuickLucerne3.8LV6N/A4 Term. Female
2008BuickLucerne4.6LV8N/A4 Term. Female
2008CadillacDTS4.6LV8N/A
2008PontiacGrand Prix3.8LV6N/A4 Term. Female
2008SuzukiXL-7N/A
2007BuickLaCrosse3.8LV6N/A
2007BuickLucerne3.8LV6N/A4 Term. Female
2007BuickLucerne4.6LV8N/A4 Term. Female
2007CadillacDTS4.6LV8N/A
2007PontiacGrand Prix3.8LV6N/A4 Term. Female
2007SuzukiXL-7N/A
2006BuickLaCrosse3.8LV6N/A
2006BuickLucerneN/A4 Term. Female
2006CadillacDTS4.6LV8N/A
2006PontiacGrand Prix3.8LV6N/A4 Term. Female
2005CadillacDeVilleN/A
2005PontiacBonneville4.6LV8N/A4 Term. Female
2005PontiacGrand PrixN/A4 Term. Female
2004BuickRegalN/A4 Term. Female
2004CadillacDeVilleN/A
2004CadillacSevilleN/A4 Term. Female
2004PontiacBonneville4.6LV8N/A4 Term. Female
2004PontiacGrand PrixN/A4 Term. Female
2003BuickRegalN/A4 Term. Female
2003CadillacDeVilleN/A
2003CadillacSevilleN/A4 Term. Female
2003OldsmobileAuroraN/A
2002BuickRegalN/A4 Term. Female
2002CadillacDeVilleN/A
2002CadillacEldoradoN/A
2002CadillacSevilleN/A
2002DodgeViperN/A
2002OldsmobileAurora4.0LV8N/A4 Term. Female
2001BuickRegalN/A4 Term. Female
2001CadillacDeVilleN/A
2001CadillacEldoradoN/A
2001CadillacSevilleN/A
2001DodgeViperN/A
2001OldsmobileAurora4.0LV8N/A4 Term. Female
2000BuickRegalN/A4 Term. Female
2000CadillacDeVilleN/A
2000CadillacEldoradoN/A
2000CadillacSevilleN/A
2000DodgeViperN/A
1999BuickLeSabreN/A
1999BuickRegalN/A4 Term. Female
1999BuickRivieraN/A
1999CadillacDeVilleN/A4 Term. Female
1999CadillacEldoradoN/A4 Term. Female
1999CadillacSevilleN/A4 Term. Female
1999DodgeViperN/A
1999Oldsmobile88N/A
1999OldsmobileAuroraN/A
1999OldsmobileLSSN/A
1999PontiacBonnevilleN/A
1998BuickLeSabreN/A
1998BuickRegalN/A4 Term. Female
1998BuickRivieraN/A
1998CadillacDeVilleN/A
1998CadillacEldoradoN/A
1998CadillacSevilleN/A
1998DodgeViperN/A
1998Oldsmobile88N/A
1998OldsmobileAuroraN/A
1998OldsmobileLSSN/A
1998OldsmobileRegencyN/A
1998PontiacBonnevilleN/A
1997BuickLeSabreN/A
1997BuickRegalN/A4 Term. Female
1997BuickRivieraN/A
1997CadillacDeVilleN/A
1997CadillacEldoradoN/A
1997CadillacSevilleN/A
1997DodgeViperN/A
1997Oldsmobile88N/A
1997OldsmobileAuroraN/A
1997OldsmobileLSSN/A
1997OldsmobileRegencyN/A
1997PontiacBonnevilleN/ABlack and Green
1996BuickLeSabreN/A
1996BuickPark AvenueN/A
1996BuickRivieraN/A
1996CadillacDeVilleN/A
1996CadillacEldoradoN/A
1996CadillacSevilleN/A
1996ChevroletCamaroN/ABlack and Green
1996Oldsmobile88N/A
1996Oldsmobile98N/A
1996OldsmobileAuroraN/A
1996OldsmobileLSSN/A
1996PontiacBonnevilleN/ABlack and Green
1996PontiacFirebirdN/ABlack and Green
1995BuickLeSabreN/A
1995BuickPark AvenueN/A
1995BuickRivieraN/A
1995CadillacDeVilleN/A
1995CadillacEldoradoN/A
1995CadillacSevilleN/A
1995ChevroletCamaroN/ABlack and Green
1995Oldsmobile88N/A
1995Oldsmobile98N/A
1995OldsmobileAuroraN/A
1995PontiacBonnevilleN/ABlack and Green
1995PontiacFirebirdN/ABlack and Green
1994BuickLeSabreN/A
1994BuickPark AvenueN/A
1994CadillacDeVilleN/A
1994CadillacEldoradoN/A
1994CadillacSevilleN/A
1994ChevroletLumina APVN/ABlack and Green
1994Oldsmobile88N/A
1994Oldsmobile98N/A
1994PontiacBonnevilleN/ABlack and Green
1993BuickLeSabreN/A
1993BuickPark AvenueN/A
1993BuickRivieraN/A
1993CadillacAllanteN/A
1993CadillacDeVilleN/A
1993CadillacEldoradoN/A
1993CadillacSevilleN/A
1993ChevroletLumina APVN/ABlack and Green
1993Oldsmobile88N/A
1993Oldsmobile98N/A
1993OldsmobileCutlass CieraN/ABlack and Green
1993PontiacBonnevilleN/ABlack and Green
1992BuickLeSabreN/A
1992BuickPark AvenueN/A
1992BuickRivieraN/A
1992CadillacDeVilleN/A
1992CadillacEldoradoN/A
1992CadillacFleetwood4.9LV8N/A4 Term. Female
1992CadillacSevilleN/A
1992ChevroletCommercial Chassis4.3LV6N/A4 Term. Female
1992ChevroletCommercial Chassis5.0LV8N/A4 Term. Female
1992ChevroletCommercial Chassis5.7LV8N/A4 Term. Female
1992ChevroletLumina APVN/ABlack and Green
1992ChevroletMetro1.3LL4N/A4 Term. Female
1992Oldsmobile88N/A
1992Oldsmobile98N/A
1992OldsmobileCutlass CieraN/ABlack and Green
1992OldsmobileCutlass Cruiser3.3LV6N/A4 Term. Female
1992OldsmobileToronadoN/A
1992PontiacBonnevilleN/ABlack and Green
1991BuickLeSabreN/A
1991BuickPark AvenueN/A
1991BuickReatta3.8LV6N/A4 Term. Female
1991BuickRivieraN/A
1991ChevroletCommercial Chassis5.7LV8N/A4 Term. Female
1991ChevroletCommercial Chassis5.0LV8N/A4 Term. Female
1991ChevroletSprint1.0LL3N/A4 Term. Female
1991ChevroletTracker1.6LL4N/A4 Term. Female
1991GMCTracker1.6LL4N/A4 Term. Female
1991Oldsmobile98N/A
1991OldsmobileCutlass CieraN/ABlack and Green
1991OldsmobileCutlass Cruiser3.3LV6N/A4 Term. Female
1991OldsmobileDelta 88N/A
1991OldsmobileToronadoN/A
1991PontiacBonnevilleN/ABlack and Green
1990BuickLeSabre3.8LV6N/A4 Term. Female
1990BuickReattaN/A
1990BuickRivieraN/A
1990CadillacCommercial Chassis4.5LV8N/A4 Term. Female
1990ChevroletSprint1.0LL3N/A4 Term. Female
1990OldsmobileCutlass Cruiser2.5LL4N/A4 Term. Female
1990OldsmobileCutlass Cruiser3.3LV6N/A4 Term. Female
1990PontiacBonnevilleN/ABlack and Green
1989BuickReattaN/A
1989BuickRivieraN/A
1989CadillacCommercial Chassis4.5LV8N/A4 Term. Female
1989ChevroletSprint1.0LL3N/A4 Term. Female
1988BuickReattaN/A
1988BuickRivieraN/A
1988CadillacCommercial Chassis4.5LV8N/A4 Term. Female
1988ChevroletNova1.6LL4N/A4 Term. Female
1988ChevroletSpectrum1.5LL4N/A4 Term. Female
1988ChevroletSprint1.0LL3N/A4 Term. Female
1988OldsmobileCutlass Cruiser2.5LL4N/A4 Term. Female
1988OldsmobileCutlass Cruiser2.8LV6N/A4 Term. Female
1988OldsmobileCutlass Cruiser3.8LV6N/A4 Term. Female
1987BuickRivieraN/A
1987ChevroletNova1.6LL4N/A4 Term. Female
1987ChevroletSpectrum1.5LL4N/A4 Term. Female
1987ChevroletSprint1.0LL3N/A4 Term. Female
1987OldsmobileCutlass Cruiser2.8LV6N/A4 Term. Female
1987OldsmobileCutlass Cruiser2.5LL4N/A4 Term. Female
1987OldsmobileCutlass Cruiser3.8LV6N/A4 Term. Female
1987OldsmobileCutlass Salon3.8LV6N/A4 Term. Female
1987OldsmobileCutlass Salon5.0LV8N/A4 Term. Female
1986BuickRivieraN/ABlack and Green
1986ChevroletNova1.6LL4N/A4 Term. Female
1986ChevroletSpectrum1.5LL4N/A4 Term. Female
1986ChevroletSprint1.0LL3N/A4 Term. Female

* 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:

120855391P1056350-28043357-4601EC52PT258PTA1378

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.