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Standard Ignition EFL166 Ambient Light SensorOE Quality 60-Day Returns
Part #: EFL166

Standard Ignition EFL166 Ambient Light Sensor

135 vehicles fit this part
Select your vehicle to confirm fitment
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Fitment: Buick, Cadillac, Chevrolet, GMC, Oldsmobile, Pontiac, and Saturn, Astro, Avalanche 1500, Avalanche 2500, Aztek, Blazer, Bravada, Envoy, Envoy XL, Equinox, Escalade, Escalade EXT, Grand Prix, Impala, Jimmy, Monte Carlo, Rendezvous, S10, Safari, Sierra 1500, Sierra 1500 HD, Sierra 2500, Sierra 2500 HD, Sierra 3500, Silverado 1500, Silverado 1500 HD, Silverado 2500, Silverado 2500 HD, Silverado 3500, Solstice, Sonoma, Torrent, and Vue
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Reliable Ambient Light Sensor for Select GM Vehicles

The Standard Ignition EFL166 Ambient Light Sensor is designed to provide accurate light detection for various General Motors models. Engineered with a clip attachment method and a durable black finish, this sensor ensures consistent performance in your Buick, Chevrolet, GMC, and other compatible vehicles.

  • Attachment Method: Clip for secure installation
  • Color/Finish: Black for seamless integration
  • Connector Type: Female plug-in with 10 connectors
  • Connector Shape: Rectangular for precise fit
  • Terminal Type: Male blade terminals, 2 in quantity
  • Contents: Includes the ambient light sensor only

Detailed Product Description

The Standard Ignition EFL166 Ambient Light Sensor is a critical component for vehicles such as the Chevrolet Silverado 1500, GMC Sierra 2500, and Cadillac Escalade. Its clip attachment method allows for straightforward mounting, while the black finish complements the vehicle’s interior design. The sensor features a female connector with 10 pins arranged in a rectangular shape, ensuring a secure and reliable electrical connection. The male blade terminals, numbering two, provide efficient signal transmission. This sensor is engineered to detect ambient light levels accurately, enabling automatic adjustments in lighting systems for improved visibility and safety.

Compatible Vehicles and Applications

  • Buick Rendezvous and Terraza
  • Cadillac Escalade and Escalade EXT
  • Chevrolet Avalanche 1500 and 2500
  • GMC Sierra 1500 HD and Sierra 3500
  • Oldsmobile Bravada
  • Pontiac Grand Prix and Aztek
  • Saturn Vue and Ion

Common Issues Addressed by This Sensor

  • Inconsistent automatic headlight activation
  • Malfunctioning interior lighting adjustments
  • Erratic dashboard illumination
  • Failure in ambient light detection affecting safety features
  • Electrical connection problems due to worn sensors

Installation Notes and Tips

Installation of the Standard Ignition EFL166 sensor requires careful handling of the clip attachment to ensure a secure fit. Verify the rectangular female connector aligns properly with the vehicle’s wiring harness. Avoid forcing the male blade terminals to prevent damage. It is recommended to disconnect the battery before installation to prevent electrical shorts. Consult the vehicle’s service manual for specific location and wiring diagrams.

Quality Assurance and Warranty

Standard Ignition parts are manufactured to meet or exceed OEM specifications, ensuring reliable performance and durability. While specific warranty details for the EFL166 sensor are not provided here, Standard Ignition typically offers coverage against defects in materials and workmanship. For exact warranty terms, refer to the product documentation or contact the manufacturer.

BrandStandard Ignition
Part NumberEFL166
Attachment MethodClip
Color/FinishBlack
Connector GenderFemale
Connector Quantity10
Connector ShapeRectangular
Connector TypePlug in
ContentsSensor
Terminal GenderMale
Terminal Quantity2
Terminal TypeBlade

This part fits 135 vehicles. Search below:

YearMakeModelLitersCylindersPositionNotes
2007BuickRendezvousN/A
2007GMCEnvoyN/A
2007PontiacGrand PrixN/A
2007PontiacSolsticeN/A
2006BuickRendezvousN/A
2006ChevroletEquinoxN/A
2006GMCEnvoyN/A
2006GMCEnvoy XLN/A
2006PontiacGrand PrixN/A
2006PontiacSolsticeN/A
2006PontiacTorrentN/A
2005BuickRendezvousN/A
2005ChevroletAstroN/A
2005ChevroletBlazerN/A
2005ChevroletEquinoxN/A
2005ChevroletImpalaN/A
2005ChevroletMonte CarloN/A
2005GMCEnvoyN/A
2005GMCEnvoy XLN/A
2005GMCJimmyN/A
2005GMCSafariN/A
2005PontiacAztekN/A
2005PontiacGrand PrixN/A
2005SaturnVueN/A
2004BuickRendezvousN/A
2004ChevroletAstroN/A
2004ChevroletAvalanche 15005.3LV8N/A
2004ChevroletAvalanche 25008.1LV8N/A
2004ChevroletBlazerN/A
2004ChevroletImpalaN/A
2004ChevroletMonte CarloN/A
2004ChevroletS10N/A
2004ChevroletSilverado 1500N/A
2004ChevroletSilverado 25005.3LV8N/A
2004ChevroletSilverado 2500 HD6.0LV8N/A
2004ChevroletSilverado 35005.7LV8N/A
2004GMCJimmyN/A
2004GMCSafariN/A
2004GMCSierra 1500N/A
2004GMCSierra 25006.0LV8N/A
2004GMCSierra 2500 HD6.0LV8N/A
2004GMCSierra 35006.0LV8N/A
2004GMCSonomaN/A
2004PontiacAztekN/A
2004SaturnVueN/A
2003BuickRendezvousN/A
2003CadillacEscalade EXTN/A
2003ChevroletAstroN/A
2003ChevroletAvalanche 15005.3LV8N/A
2003ChevroletAvalanche 25008.1LV8N/A
2003ChevroletBlazerN/A
2003ChevroletImpalaN/A
2003ChevroletMonte CarloN/A
2003ChevroletS10N/A
2003ChevroletSilverado 1500N/A
2003ChevroletSilverado 1500 HD6.0LV8N/A
2003ChevroletSilverado 25005.3LV8N/A
2003ChevroletSilverado 2500 HD6.0LV8N/A
2003ChevroletSilverado 35005.7LV8N/A
2003GMCJimmyN/A
2003GMCSafariN/A
2003GMCSierra 1500N/A
2003GMCSierra 1500 HD6.0LV8N/A
2003GMCSierra 25006.0LV8N/A
2003GMCSierra 2500 HD6.0LV8N/A
2003GMCSierra 35006.0LV8N/A
2003GMCSonomaN/A
2003PontiacAztekN/A
2002BuickRendezvousN/A
2002CadillacEscaladeN/A
2002CadillacEscalade EXTN/A
2002ChevroletAstroN/A
2002ChevroletAvalanche 15005.3LV8N/A
2002ChevroletAvalanche 25008.1LV8N/A
2002ChevroletBlazerN/A
2002ChevroletImpalaN/A
2002ChevroletMonte CarloN/A
2002ChevroletS10N/A
2002ChevroletSilverado 1500N/A
2002ChevroletSilverado 1500 HD6.0LV8N/A
2002ChevroletSilverado 25005.3LV8N/A
2002ChevroletSilverado 2500 HD6.0LV8N/A
2002ChevroletSilverado 35005.7LV8N/A
2002GMCJimmyN/A
2002GMCSafariN/A
2002GMCSierra 1500N/A
2002GMCSierra 1500 HD6.0LV8N/A
2002GMCSierra 25006.0LV8N/A
2002GMCSierra 2500 HD6.0LV8N/A
2002GMCSierra 35006.0LV8N/A
2002GMCSonomaN/A
2002PontiacAztekN/A
2001ChevroletAstroN/A
2001ChevroletBlazerN/A
2001ChevroletImpalaN/A
2001ChevroletMonte CarloN/A
2001ChevroletS10N/A
2001ChevroletSilverado 1500N/A
2001ChevroletSilverado 1500 HD6.0LV8N/A
2001ChevroletSilverado 25005.3LV8N/A
2001ChevroletSilverado 2500 HD6.0LV8N/A
2001ChevroletSilverado 35005.7LV8N/A
2001GMCJimmyN/A
2001GMCSafariN/A
2001GMCSierra 1500N/A
2001GMCSierra 1500 HD6.0LV8N/A
2001GMCSierra 25006.0LV8N/A
2001GMCSierra 2500 HD6.0LV8N/A
2001GMCSierra 35006.0LV8N/A
2001GMCSonomaN/A
2001OldsmobileBravadaN/A
2001PontiacAztekN/A
2000CadillacEscaladeN/A
2000ChevroletAstroN/A
2000ChevroletBlazerN/A
2000ChevroletImpalaN/A
2000ChevroletMonte CarloN/A
2000ChevroletS10N/A
2000ChevroletSilverado 1500N/A
2000ChevroletSilverado 25005.3LV8N/A
2000GMCJimmyN/A
2000GMCSierra 1500N/A
2000GMCSierra 25005.3LV8N/A
2000GMCSonomaN/A
2000OldsmobileBravadaN/A
1999CadillacEscaladeN/A
1999ChevroletBlazerN/A
1999ChevroletS10N/A
1999ChevroletSilverado 1500N/A
1999ChevroletSilverado 25005.3LV8N/A
1999GMCJimmyN/A
1999GMCSierra 1500N/A
1999GMCSierra 25005.3LV8N/A
1999GMCSonomaN/A
1999OldsmobileBravadaN/A

* 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:

12450120AHS100FC756SU8209

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