The crankshaft position sensor works by measuring the position of the engine crankshaft and the rotation speed.
Over time, there may be a need to replace the crankshaft position sensor. When the replacement is done, you should relearn/reset the sensor, but what happens if you don’t relearn the crankshaft position sensor?
If you don’t relearn the crankshaft position sensor, the car won’t start and there may also be an acceleration issue that can alter your driving experience.
What Happens if You Don’t Relearn Crankshaft Position Sensor?
If you don’t relearn the crankshaft position sensor:
- The Car Won’t Start: Not relearning the crankshaft position sensor affects the ECU because the ECU relies on it for some relaxing power. The ECU handles a car’s ignition therefore if anything is wrong with it, the car will not start because the ignition will be affected also.
- The Engine Can Go Haywire: An issue with the ECU can cause it to send wrong signals to the car which may also cause the engine to go haywire. When an inappropriate signal is sent to the car, not only will the car not start, but it may also explode.
- Acceleration Disorder: There can be an uncontrollable increase or decrease in acceleration when you don’t relearn the crankshaft position sensor. Not relearning the crankshaft sensor makes the crankshaft unreliable and this unreliability can make you lose control of the car’s acceleration.
- High Fuel Consumption: If you fail to relearn your crankshaft position sensor after having a replacement, it will continue to use the readings from the damaged sensor, hence, the car will continue to consume more fuel until the reset is done.
- Engine Misfire: The engine will definitely misfire if the crankshaft sensor is not reprogrammed immediately after a replacement is done, because the car will continue to use the readings from the removed sensor.
When Should You Relearn Your Crankshaft Position Sensor?
When a diagnostic code of P1336 is present then you know it’s time to relearn/reprogram the crankshaft position sensor. You can also relearn your crankshaft position sensor when there is a replacement of the sensor whether there is a trouble code or not.
How Do You Manually Relearn a Crankshaft Position Sensor?
Resetting a crankshaft position sensor manually means relearning without a scanner and this can be done by going through the following process;
- First, switch off all accessories in the car and ensure that the coolant and air temperature sensors are within 5c of one another.
- Once this is done you can start the engine.
- Putting the engine in neutral or park, allow it to idle for at least 2 minutes.
- After which you should put it at part throttle and then accelerate the car to 55mph.
- Drive and maintain this speed for at least 10 mins, this will give the engine enough time to reach its operating temperature.
- Once this speed has been reached you should still drive around for at least 5 minutes.
- You can then reduce the speed to 45mph for at least a minute. This should be done in 4 cycles minus the brake and without speed specifications.
- Accelerate the car again at 55mph for at least 2mins
- Finally, you should stop the car and allow it to idle for at least 2 minutes.
How Long Does It Take to Relearn a Crankshaft Position Sensor?
The length of time it takes to relearn a crankshaft position sensor largely depends on the car and the scanner. Irrespective of the car, relearning a crankshaft position sensor will take less than 30 minutes or up to an hour.
When using a scanner to relearn the crankshaft position sensor, scanning in itself takes up roughly 10mins of the time. With or without the scanner you should be done within 30mins or more.
Will Crankshaft Sensor Reset if I Disconnect the Battery?
No, the crankshaft position sensor will not reset of you disconnect the battery, it will only reset the car’s ECU and clear the fault codes caused by the damaged sensor.
Disconnecting the battery will clear the fault codes caused by the damaged crankshaft position sensor if there is an error trouble code. To do this, you will need to disconnect the negative battery terminal and allow the car to sit for at least an hour.
What Scan Tool Can Relearn Crankshaft Position Sensor?
Choosing the best OBD 2 scanner for your car can be hard as there are lots of them in the market today. Not to worry, here we will take a look at some scan tools that can relearn the crankshaft position sensor.
Launch CRP129E Scan Tool
The first choice of a scan tool for relearning the crankshaft position sensor is the Launch CRP129E. This scan tool is known as the best not only because it is easy to use, but because it can also auto-diagnose the car’s engine and emission test.
If you buy a launch CRP129E from an authentic dealer you will get free lifetime updates and a 5-year warranty. The launch CRP129E gives you access to data codes from over 60 carmakers and 1,000 models plus it also supports Wi-Fi.
Autel MaxiTPMS TS501 TPMS AUTOMOTIVE Scan Tool
This scan tool also has the capability to relearn the crankshaft position sensor. From the name you can tell that it is an automotive scan tool capable of providing relearning procedures for some sensors like the crankshaft sensor.
The Autel TS501 offers various programming options such as; auto create IDs or cloning sensor IDs by connecting with the OBD2 cord.
In comparison to other scanners, the Autel TS501 is said to give the most accurate and fastest results. For every Autel TS501 scan tool, there is a free lifetime software update and it also supports many languages.
INNOVA 3160RS Pro OBD2 Scanner
Another scan tool that can relearn the crankshaft position sensor is the INNOVA 3160RS, this scan tool has the capabilities to support the OBD 1 and OBD 2.
It is rare to find a scanner that can support both, more reason why it is one of the best scanners out there. This scanner is able to diagnose issues in four different central systems by accessing the car’s ECU.
Although the INNOVA 3160RS is expensive, it is definitely worth every penny spent and is also user-friendly. It supports 3 different languages and is able to check a battery’s health in hybrid cars.
It is important to note that these are not the only scanner that can relearn the crankshaft position sensor. These 3 are just recommendations that will help you in making the best decision when buying a scanner. You should also make sure to buy the one that will work with your type of car.
Conclusion
Using a scanner or manually relearning the crankshaft position sensor is quite easy but if it seems like too much work and something you can’t handle, you can get help. Better to get help and pay than cause more problems in the car.