The crankshaft position sensor is a sensor that monitors the crankshaft. It is installed in a car to monitor the rotational position of the crankshaft to determine the engines RPM, therefore, when this sensor goes bad, it should be replaced immediately to avoid damaging other components of the engine.
However, after the crankshaft position sensor is replaced, you need to reset the crankshaft sensor to start getting readings from the newly installed sensor, so the question is, how do you perfect this reset? What is the best procedure to follow? Will disconnecting the battery reset crankshaft sensor?
No, disconnecting the battery will not reset the crankshaft position sensor because unlike the car’s ECU, the sensor does not have an internal memory that can be reset by disconnecting the battery. Therefore, you can only reset a crankshaft sensor with an OBD-II scanner tool.
Will Disconnecting Battery Reset Crankshaft Sensor?
Having your battery disconnected will not reset the crankshaft sensor. It can clear the stored codes in the cars ECU but will not reset the sensor. You have to perform the reset the recommended way as instructed by the manufacturer.
This is because, a crankshaft position sensor, just like the name implies, is a sensor that monitors the rotational speed of the crankshaft and sends reading information to the car’s computer about the rotational speed as well as the position of the crankshaft hence determining the engines RPM which in turns calculate the timing for the fuel injector as well as the ignition.
If the sensor goes bad, you will find it difficult starting the car because the sensor is no longer able to send the correct readings of the crankshaft to the car’s computer, therefore, there’s no way to determine the engines RPM to calculate the timing for fuel injector and the ignition. This sensor is not something you can easily reset by just disconnecting the battery.
Best Way to Reset Crankshaft Sensor
Since disconnecting the battery cannot reset the crankshaft position sensor, therefore, the best way to reset the crankshaft sensor would be to use an OBD-II scanner tool to perform the reset. To do this, follow the procedures below:
- Connect the scanner to your car and turn the ignition on, do not start the car
- Depending on your scanner, once it finally boots up, follow the steps provide for you and select your car brand, model, and manufactured year, and ensure to add the VIN if it requires you to do so.
- Select diagnosis, select control unit, select power train, and select the ECM (Engine control module) and allow it to run
- Click on the Special function and allow it to run
- You will see the cam crank relearn, click on it
- Start your engine
- Depending on your brand of car, ensure that the engine cooling temperature is within the required number the scanner will tell you
- Once the temperature is where it should be, the relearn will start and complete itself without any issue.
Following this procedure accurately as explained will reset the crankshaft sensor.
When to Reset Crankshaft Sensor
You can reset the crankshaft position sensor after you complete a replacement job. Immediately you’re done replacing the sensor, the next thing to do would be to reset the sensor to enable the control module pick up the new readings from the new sensor.
You must do this to complete the job otherwise, you may continue to experience the same problems you used to experience before the sensor was replaced.
What Damages Crankshaft Position Sensor?
Here are the reasons why your position sensor went bad:
1. Old Age
The crankshaft position sensor is not made to last forever, as times goes on, with use, the sensor can get old and go bad. When this happens, the best solution would be to have the sensor replaced.
2. Wear and Tear
Wear and tear is another reason why a crankshaft position sensor can go bad. The wear and tear can happen because of the number of years the sensor has been in use. When this happens, the best solution would be to have the sensor replaced with another one.
3. Bad Reluctor Wheel
When the reluctor wheel of the sensor goes bad, it will prevent the sensor from performing the way it used to.
4. Bad Connections and Wiring
If the crankshaft sensor connectors are not properly connected, it can prevent the sensor from working the way it should. The same goes with bad wiring. If there’s anything wrong with the wiring, it will affect the sensor.
5. To much Heat
A crankshaft sensor can get bad if it’s exposed to too much heat. This is the reason why you should avoid driving an overheating vehicle. With such heat, it can damage the sensor
6. Dirt
The crankshaft position sensor can damage if it’s exposed to too much dirt. The dirt and debris can be because of long usage. Oil can also make its way to the sensor hence damaging it with time.
Don’t forget that when the sensor starts to fail or has failed, you will experience symptoms like:
- Hard starting: You may find it difficult starting the car
- Bad Gas Mileage: You will start having bad gas mileage. You will see yourself buying more fuel than you use to. The fuel consumption will terrify your life.
- Misfire: The engine may start to misfire terribly. A bad crankshaft sensor will definitely cause a misfire
- Lose of Power: Your car will start to under perform. The under performance will be too obvious that you will notice it. No one wants to drive a car with a reduced engine power.
- Check Engine Light: The check engine warning light will appear on you dashboard immediately, warning you about a problem with your engineer.
Can a Bad Battery Cause Crankshaft Sensor Problems?
Yes, a bad battery can cause crankshaft position sensor problems especially if the battery is too bad that its discharging low voltage to the car. The P0335 (Crankshaft Position Sensor Circuit) and/or P0340 (Camshaft Position Sensor Circuit) code will come on due to inconsistent rotational speed of the engine’s crankshaft.
Will an Engine Run without a Crankshaft Position Sensor?
An engine will not be able to function well without a crankshaft sensor. The engine will continue to misfire terribly while consuming all the fuel in the car. The said engine will loose its power and will struggle to perform on the road. It’s not a good idea to leave the engine running without a crankshaft sensor.
Final Thoughts
Disconnecting the batter will not reset the crankshaft sensor because the sensor is not the ECU of the car that has memory and stores code. After replacing the sensor, you must reset the sensor with an OBD-II scanner. This is a sure way of performing the reset.