How to Reset Crankshaft Position Sensor 2023

What is Crankshaft Position Sensor

The crankshaft position sensor is one of the most important sensors in the engine electronic control system, which provides the ignition moment (ignition advance angle), confirms the crankshaft position signal, and is used for detecting the piston top stop, crankshaft angle and engine speed.

The structure of crankshaft position sensors varies with different models and can be divided into three categories: magnetic pulse, photoelectric and Hall. It is usually installed in the front end of the crankshaft, the front end of the camshaft, on the flywheel or in the distributor.

What Does a Crankshaft Position Sensor Do

The function of the crankshaft position sensor has the following 5 points:

1. The crankshaft position sensor can detect the engine speed, determine the injection volume and ignition advance angle, to avoid the phenomenon of reduced injection volume.

2. The crankshaft position sensor can detect the engine reference cylinder reference position, cylinder order discrimination.

3. The crankshaft position sensor can detect the crankshaft rotation angle, determine the piston running in any position, determine the ignition moment and the fuel injection moment, which will help the car ignition of the best moment.

4. The crankshaft position sensor in addition to controlling the fuel injection and ignition, also used for idling control, fuel evaporation control, etc., the reasonable use of the crankshaft position sensor can be a more accurate understanding of the car's working condition.

5. The crankshaft rotation angle and engine speed signals are collected and inputted into the ECU in order to determine the injection sequence, injection timing, ignition sequence, ignition timing, and then determine whether the engine has misfire according to the size of the crankshaft rotation angle fluctuation monitored by the signals.

How to Reset Crankshaft Position Sensor (Part 1)

Resetting a crankshaft position sensor (CPS) typically involves either relearning its position or replacing it if it's malfunctioning. Here are general steps you might follow:

Relearning the Position:

• Disconnect the Battery: Ensure the car's battery is disconnected to prevent any electrical issues.
• Locate the CPS: Find the CPS in your vehicle. It's usually near the crankshaft or the flywheel/drive plate.
• Inspect and Clean: Check for any debris or dirt around the sensor. Clean it if necessary to ensure accurate readings.
• Reconnect Battery: After cleaning, reconnect the battery.
• Reset the ECU: Some vehicles require resetting the Engine Control Unit (ECU) to relearn the CPS. This can be done by disconnecting the battery for a while (approximately 30 minutes) or using a diagnostic tool to clear error codes.
• Follow Manufacturer Instructions: Some vehicles might have specific procedures for CPS relearning. Check the vehicle's manual or online resources for any manufacturer-recommended steps.

Replacement:

If the sensor is faulty or damaged beyond repair, replacement might be necessary. Follow these steps:

• Purchase a Replacement: Get the correct replacement CPS for your vehicle.
• Locate and Remove the Old Sensor: Disconnect the electrical connector and unbolt the sensor from its mounting position.
• Install the New Sensor: Install the new sensor in the correct position and secure it with bolts.
• Reconnect Battery and Reset ECU: Follow the same steps as above for resetting the ECU and reconnecting the battery.

How to Reset Crankshaft Position Sensor (Part 2)

Generally, there's no direct "reset" for a CPS like you might reset an electronic device.

The CPS is an integral part of the engine management system, and it primarily relays information to the engine control unit (ECU) to ensure proper engine function. If it's malfunctioning, replacing or relearning it might be necessary.

Here's a more general and simplified approach to addressing CPS issues:

Troubleshooting Steps:

Diagnostic Scan: Use an OBD-II scanner to retrieve trouble codes associated with the CPS. This can help pinpoint the specific issue before attempting any reset or repair.

Visual Inspection: Check the CPS for any visible damage, loose connections, or debris. Cleaning any dirt around the sensor might help if it's affecting its performance.

Consult Professional Help: Given the sensitivity of the CPS and its critical role in engine performance, consulting a professional mechanic or dealership might be the best course of action. They have the tools and expertise to diagnose and fix CPS issues accurately.

Potential Reset Procedures: In some cases, relearning the CPS might involve specific procedures outlined by the manufacturer. This could involve using diagnostic tools to reset the ECU or performing certain driving cycles to help the ECU relearn the sensor's data. These procedures are often specific to certain car models and might not apply universally.

Replacement: If the sensor is indeed faulty, it might need replacement. Doing so typically involves locating the sensor, disconnecting it, replacing it with a new one, and potentially following specific calibration or relearning processes as outlined in the car's manual.

Caveats:

Vehicle-Specific Procedures: Always refer to the vehicle's manual or official resources for manufacturer-recommended procedures.

Electrical Safety: When working with sensors and electrical components, ensure the battery is disconnected to prevent electrical issues.

Professional Assistance: For complex engine-related issues, seeking help from a certified mechanic or dealership is often the safest and most effective route.

Remember, while online resources can provide guidance, the specifics can vary widely between car models and years. When in doubt, seeking professional help ensures the issue is addressed accurately and safely.

How to Reset Crankshaft Position Sensor Without Scanner

Resetting the CPS without a scanner might not resolve underlying issues with the sensor's functionality. 

Here’s the video,

You could try a few general methods below,

Method 1: Battery Disconnect

Disconnect Battery: Disconnect the car's battery and wait for about 15-30 minutes. This might reset the vehicle's computer system, including the memory related to the CPS.

Reconnect Battery: Reconnect the battery and start the car. Drive it for a short distance to see if the CPS-related issues persist.

Method 2: Driving Cycle Reset

Turn off Accessories: Start with all accessories turned off.

Drive at Steady Speeds: Drive the car on the highway or a road where you can maintain a consistent speed for about 15-20 minutes at various speeds, including 45-55 mph.

Cruise and Decelerate: Maintain the speed, then gradually decelerate without using brakes to slow down. Repeat this process a few times.

Stop and Restart: Turn off the engine, wait a few minutes, and then restart the car. Check if the CPS-related issues persist.

Method 3: Physical Inspection and Cleaning

Inspect the CPS: Check the CPS for any visible damage, loose connections, or debris. Clean it carefully if there's any dirt or buildup around the sensor.

Disconnect and Reconnect: Disconnect the CPS (after disconnecting the battery) and reconnect it securely. Sometimes, poor connections can cause issues.

FAQs

Q: Can cleaning the crankshaft position sensor reset it?

A: Cleaning the sensor might improve its performance if the issue is due to dirt or debris affecting its function. However, it won't reset the sensor itself. It might be a temporary fix, and if the sensor continues to malfunction, replacement may be necessary.

Q: How can I diagnose a faulty crankshaft position sensor?

A: Symptoms of a faulty sensor may include engine misfires, stalling, difficulty starting the engine, or the Check Engine Light illuminating. Diagnostic tools can also help pinpoint sensor issues by reading error codes stored in the vehicle's computer.

Q: What steps can I take if the crankshaft position sensor needs resetting?

A: If you suspect a problem with the sensor, inspect it for damage or debris, clean the area around it, and ensure it's properly connected. If issues persist, consider consulting a mechanic or replacing the sensor.

Q: Can disconnecting the battery reset the crankshaft position sensor?

A: Disconnecting the battery might reset the vehicle's computer and clear stored error codes related to sensor issues, but it won't reset or fix the sensor itself. If there's a persistent problem with the sensor, it might need replacement.