Delphi SS20137 Sensor

Delphi SS20137 Sensor

The Delphi SS20137 is a high‑performance wheel speed sensor designed specifically for the rear axle of Mercedes-Benz vehicles, including the A‑Class, Vaneo, and Monocab models produced between 1997 and 2005. This passive sensor plays a critical role in the vehicle’s Anti‑Lock Braking System (ABS), ensuring safe and reliable braking by accurately measuring wheel rotation speed.

Key Functionalities

• Passive Operation: The sensor does not require an external power source; it generates its signal through magnetic induction as the wheel rotates.
• High Accuracy: Delivers precise wheel‑speed data to the ABS control unit, enabling optimal brake modulation and preventing wheel lockup during emergency stops.
• Robust Construction: Built with a durable housing that resists vibration, temperature extremes, and exposure to road debris.
• Compact Design: Fits seamlessly into the existing sensor bay without requiring modifications to the vehicle’s suspension or wheel assembly.

Compatibility Overview

The SS20137 is engineered for a wide range of Mercedes-Benz rear‑wheel configurations. It matches the original equipment specifications (OE) and is suitable for:

• MERCEDES‑BENZ A‑CLASS (1997–2004)
• VANELO (2002–2005)
• MONOCAB variants of the A‑Class platform
• Both left and right rear wheel positions, typically sold as a pair for full system redundancy.

Installation Guide

1. Safety First: Raise the vehicle securely using jack stands and disconnect the battery to prevent accidental electrical discharge.
2. Remove Old Sensor: Locate the rear wheel speed sensor housing on the axle. Unscrew the mounting bolts, carefully detach the wiring harness, and slide the old sensor out of its bay.
3. Prepare New Sensor: Inspect the SS20137 for any visible damage. Ensure the magnetic core is intact and that the connector pins are clean.
4. Install: Position the new sensor into the housing, aligning it with the wheel’s magnetic field. Tighten the mounting bolts to the manufacturer’s torque specification (typically 12–15 Nm).
5. Reconnect Wiring: Attach the harness connector, ensuring a secure fit and proper alignment of pins.
6. Test Functionality: Reconnect the battery, start the engine, and verify that the ABS light remains off. Use a diagnostic scan tool to confirm that wheel‑speed readings are within expected ranges.

Diagnostic Tips

• If the ABS warning lamp illuminates after installation, double‑check the sensor alignment and wiring continuity.
• A faulty sensor may cause irregular brake modulation or a loss of ABS functionality; replace immediately to maintain safety.
• Use an oscilloscope or specialized wheel‑speed tester to verify signal integrity if troubleshooting persists.

Performance Benefits

Choosing the Delphi SS20137 ensures:

• Consistent Brake Response: Accurate speed data allows the ABS module to modulate brake pressure precisely, reducing stopping distances on slippery surfaces.
• Long‑Term Reliability: The sensor’s robust construction withstands harsh operating conditions, minimizing maintenance intervals.
• Seamless Integration: As an OEM‑approved part, it maintains the vehicle’s original performance characteristics without compromising compatibility.

Technical Specifications

Conclusion

The Delphi SS20137 is a reliable, high‑quality wheel speed sensor that delivers precise ABS performance for Mercedes-Benz rear axles. Its passive design, durable construction, and strict adherence to OEM specifications make it an ideal choice for both professional technicians and knowledgeable vehicle owners seeking to maintain optimal braking safety.