Standard Motor Products ALS35 Speed Sensor Instruction Manual

1. Product Overview

The Standard Motor Products ALS35 Speed Sensor is a critical automotive component designed to accurately measure the rotational speed of a vehicle's wheels or transmission. This data is essential for various vehicle systems, including the Anti-lock Braking System (ABS), traction control, and speedometer. Manufactured with high-quality materials, this sensor ensures reliable performance and durability.

This image displays the complete Standard Motor Products ALS35 Speed Sensor assembly. It features the primary sensor component, a durable black wiring harness, and a grey electrical connector. The sensor is designed for precise measurement of rotational speed in automotive applications.

Key Features:

• Product Type: Auto Part
• Package Quantity: 1
• Package Weight: 0.7 lbs
• Country Of Origin: China

2. Setup and Installation

Proper installation of the speed sensor is crucial for its correct function and vehicle safety. It is recommended that installation be performed by a qualified automotive technician.

Installation Steps (General Guidelines):

1. Safety First: Ensure the vehicle is safely lifted and supported on jack stands. Disconnect the vehicle's battery to prevent electrical hazards.
2. Locate Old Sensor: Identify the location of the existing speed sensor. This can vary depending on the vehicle's make and model (e.g., wheel hub, transmission).
3. Disconnect Wiring: Carefully disconnect the electrical connector from the old sensor. Avoid pulling directly on the wires.
4. Remove Old Sensor: Unbolt or unclip the old sensor from its mounting point. Be aware that some sensors may be seized due to corrosion.
5. Clean Mounting Area: Thoroughly clean the mounting surface to ensure proper seating of the new sensor and to prevent debris from interfering with its operation.
6. Install New Sensor: Insert the new ALS35 sensor into the mounting hole. Secure it with the appropriate bolts or clips, ensuring it is seated firmly.
7. Connect Wiring: Reconnect the electrical connector to the new sensor, ensuring a secure and tight connection.
8. Route Wiring: Route the sensor wiring along the original path, securing it with any clips or ties to prevent chafing or damage.
9. Reconnect Battery: Reconnect the vehicle's battery.
10. Test System: Start the vehicle and check for any warning lights (e.g., ABS light, check engine light). Perform a test drive to confirm proper operation of the speedometer and other related systems.

Always refer to your vehicle's specific service manual for detailed installation instructions.

3. Operation

The Standard Motor Products ALS35 Speed Sensor operates by detecting the rotational speed of a component, typically a wheel or transmission output shaft. It generates an electrical signal proportional to this speed, which is then sent to the vehicle's Engine Control Unit (ECU) or other control modules.

This signal is vital for:

• Anti-lock Braking System (ABS): The ABS uses speed sensor data to detect if a wheel is locking up during braking, allowing it to modulate brake pressure and prevent skidding.
• Traction Control System (TCS): TCS utilizes speed sensor input to detect wheel slip during acceleration, applying brakes or reducing engine power to maintain traction.
• Vehicle Stability Control (VSC/ESC): These systems use speed sensor data, along with other inputs, to help maintain vehicle stability during cornering or sudden maneuvers.
• Speedometer and Odometer: The sensor's signal is often used to provide accurate vehicle speed readings to the dashboard speedometer and to track mileage on the odometer.
• Transmission Control: In some vehicles, speed sensor data assists the transmission control module in determining optimal shift points.

The sensor is a passive component that requires no user interaction once installed. Its continuous and accurate operation is essential for the safety and performance of your vehicle's advanced systems.

4. Maintenance

Speed sensors like the ALS35 are generally maintenance-free components. However, their performance can be affected by environmental factors and physical damage.

General Maintenance Tips:

• Regular Inspection: During routine vehicle maintenance (e.g., tire rotations, brake inspections), visually inspect the sensor and its wiring for any signs of damage, corrosion, or loose connections.
• Keep Clean: While designed to withstand harsh conditions, excessive buildup of dirt, mud, or road salt on the sensor head can potentially interfere with its signal. If accessible, gently clean the sensor head with a soft cloth and appropriate automotive cleaner.
• Protect Wiring: Ensure the wiring harness is securely fastened and not exposed to sharp edges, excessive heat, or moving parts that could cause chafing or damage.
• Avoid Impact: Protect the sensor from physical impact, especially during wheel or suspension work.

If a sensor is suspected of being faulty, it is typically replaced rather than repaired.

5. Troubleshooting

Malfunctions of a speed sensor can lead to various issues, often indicated by dashboard warning lights or incorrect vehicle behavior. Below are common symptoms and potential causes related to a faulty speed sensor.

Common Symptoms of a Faulty Speed Sensor:

• ABS Warning Light On: This is the most common indicator of an issue with a wheel speed sensor.
• Traction Control Light On: Similar to ABS, a faulty speed sensor can trigger the traction control warning.
• Inaccurate or Erratic Speedometer: The speedometer may read incorrectly, fluctuate wildly, or stop working entirely.
• Transmission Shifting Problems: Some automatic transmissions rely on speed sensor input for proper shifting, and a faulty sensor can cause harsh or incorrect shifts.
• Check Engine Light (CEL): While less common for speed sensors directly, some vehicle systems may trigger a CEL if speed data is missing or incorrect.
• Reduced Braking Performance: Although the vehicle can still brake, the ABS system will be disabled, potentially leading to wheel lock-up during hard braking.

Troubleshooting Steps:

1. Check for Diagnostic Trouble Codes (DTCs): Use an OBD-II scanner to retrieve any stored codes. Codes like C0035, C0040, etc., often point directly to a specific wheel speed sensor issue.
2. Visual Inspection: Inspect the sensor and its wiring for visible damage, corrosion, or loose connections. Check the sensor's mounting for proper seating.
3. Clean Sensor Head: If accessible, gently clean any debris from the sensor's tip and the tone ring (if applicable).
4. Test Sensor Resistance/Voltage: If you have a multimeter and the vehicle's service manual, you can test the sensor's resistance or signal output. Note that active sensors (most modern ones) require specific diagnostic tools for accurate testing.
5. Professional Diagnosis: If basic checks do not resolve the issue or if you lack the necessary tools, it is highly recommended to have the vehicle diagnosed by a professional automotive technician. They have specialized equipment to accurately pinpoint sensor failures.

Note: A faulty speed sensor typically requires replacement. Attempting to repair a damaged sensor is generally not recommended.

6. Specifications

Detailed specifications for the Standard Motor Products ALS35 Speed Sensor:

7. Warranty and Support

Specific warranty information for the Standard Motor Products ALS35 Speed Sensor is not provided within this manual. For details regarding warranty coverage, terms, and conditions, please refer to the official Standard Motor Products website or contact their customer support directly.

For technical support, installation assistance, or further inquiries, please visit the manufacturer's official website or consult a certified automotive technician.