Standard Ignition S2540 Ignition Knock (Detonation) Sensor Connector

Brand Standard Ignition S2540
Weather Resistant No
Bend Angle (Deg.) 0
Connector Gender Female + male
Connector Quantity 2
Connector Shape Rectangular
Gauge 18
Harness Length (mm.) 160
Harness Length - cm 16
Harness Length - inches 6.5
Housing Length (in) 1 1/2
Terminal Gender Female + male
Terminal Quantity 3
Terminal Type Blade
Weatherproof Sealed Yes
Wire Gauge (ga) 18
Wire Quantity 2
Fits Subaru · 13 vehicles

Weatherproof sealed. Helps keep the connector protected from moisture and contamination.

Blade terminals. Uses a 3-terminal blade design for a secure electrical connection.

Rectangular connector. Compact shape with a 6.5-inch harness for straightforward routing.

Cross-references Standard Ignition S2540, CONB11318 and EC2451 for the same application. See all 4.

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Ignition Knock Sensor Connector for Subaru

Standard Ignition S2540 is a weather-sealed ignition knock sensor connector built for Subaru applications that need a secure electrical connection at the detonation sensor. It is a rectangular, 2-connector harness with blade terminals and 18-gauge wiring for a direct-fit style repair.

Compatible with 1999-2002 Subaru Forester, 1999-2002 Subaru Impreza, 1999-2001 Subaru Legacy, and 2000-2001 Subaru Outback, this Standard Ignition S2540 connector supports clean signal transfer in knock sensor circuits.

  • Part number: S2540
  • Ignition knock (detonation) sensor connector
  • Rectangular connector shape with female + male connector gender
  • Weatherproof sealed design
  • 18-gauge wire construction with 160 mm harness length
  • Blade terminal type with 3 terminals
  • Housing length: 1 1/2 in.

Detailed Product Overview

Standard Ignition S2540 is designed for Subaru knock sensor wiring repairs where the original connector is damaged, brittle, or no longer making consistent contact. The 2-connector layout, 3 blade terminals, and sealed housing help maintain a stable electrical interface in the emission control circuit. This part cross-references PT2525 and EC2451 for the same application.

Use S2540 when servicing Subaru Forester, Impreza, Legacy, or Outback models from the listed years and you need a replacement connector that matches the original harness style and terminal configuration.

Common Problems This Part Can Address

  • Broken or cracked knock sensor connector housing
  • Intermittent detonation sensor signal
  • Corroded or loose terminal contact
  • Damaged wiring near the sensor connector
  • Check engine light concerns related to knock sensor circuit faults

Installation Notes and Tips

Verify connector shape, terminal style, and harness length before installation. Match the existing Subaru knock sensor connector layout and inspect the mating terminals for corrosion or heat damage before connecting the new harness. Confirm proper pin alignment and secure the sealed connection fully to maintain circuit integrity.

Quality Assurance

Standard Ignition is a recognized aftermarket source for electrical and emission control components. S2540 is built to meet the fitment and connector specifications listed for the supported Subaru applications.

This part fits 13 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersNotes
2002SubaruForester
2002SubaruImpreza2.5LH4
2001SubaruForester
2001SubaruImpreza
2001SubaruLegacy2.5LH4
2001SubaruOutback2.5LH4
2000SubaruForester
2000SubaruImpreza
2000SubaruLegacy2.5LH4
2000SubaruOutback
1999SubaruForester
1999SubaruImpreza
1999SubaruLegacy2.5LH4
Directly replaces or cross-references 4 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
Standard Ignition — S2540CONB11318EC2451PT2525