The crank sensor is an electronic sensor that tells your vehicle’s engine control unit (ECU) how fast the engine is turning, and, in turn, this determines the engine’s speed. The ECU also receives information from other sensors, such as the intake air temperature sensor and the throttle position sensor, which also help determine the actual engine speed.
Kicking off this post about how to check your crank sensor with a multimeter, it’s important to understand that a crank sensor doesn’t just fail: it might work, or it may not.
Checking the Crank Sensor
Checking a crank sensor with a multimeter is a great way to diagnose a vehicle that is stalling or running poorly. The sensor is wired directly to the ignition coil and used to help the engine start. If the crank sensor is not working, the vehicle may not crank over or may stall after a short drive. (This is a very common problem on older vehicles.) As with all electrical components, the sensor should be checked with a multimeter before replacement.
Here are the steps on how to check a crank sensor with a multimeter:
- Ready your multimeter. – You’re going to want to grab a multimeter. If you don’t have one yet, you can always get an affordable multimeter at legit online stores.
- Locate the crank sensor. – You’ll want to grab the crank sensor, which is a large silver cylinder with a copper coil on the top. The sensor is going to be connected to the car’s wiring harness. To find the correct wire, you’ll want to start with a spark plug wire. If the car cranks but doesn’t start, the problem is likely in the wiring harness. If the car starts but then loses power, the problem is probably with the crank sensor. If you are unsure which it is, you can always refer to your vehicle’s manual.
- Disconnect the sensor. – Disconnect the crank sensor from the wiring harness and set the multimeter to the 20-volt range.
- Touch the wire. – Touch the positive wire to the positive terminal of the battery and place the negative probe of the multimeter on the negative terminal of the battery to test the battery.
- Consult first. – Be sure to consult your manual before attempting to connect the multimeter to the sensor, as some older crank sensors can be damaged by excessive voltages.
Now that you know how to check a crank sensor with a multimeter, you can make sure that you buy the right one and get it quickly. Be sure to double-check all the wires and work carefully, especially if you are working with high voltage and/or electronics. Always check the documentation to make sure that you are installing the sensor correctly.
What Is A Crank Sensor?
A crank sensor is a device that measures the rotational speed of an engine. It is usually used in conjunction with a cam sensor. The two work in synergy to provide accurate measurement data to the engine control unit. It is a very delicate sensor in your car, and when problems occur with a crank sensor, it is usually because it has been bumped or dropped or exposed to heavy vibration. This can cause the sensor’s internal components to break, or in some cases, the sensor itself to short.
If you have checked that the sensor is getting power and ground, you have checked that the wiring is good, and the engine is still not starting, you should check the sensor itself to make sure that the components are intact.
The crank sensor is an integral part of the car’s timing control system. A crank sensor monitors the position of the crankshaft (or crank) in a car’s engine. The sensor is usually mounted on the end of the crank.
There are two main types of crank sensor:
- Mechanical sensor – uses a toothed or ratcheting wheel. It is often used in cars or trucks, and it measures the wheel rotation speed. It is also a device that senses the rotation of a crankshaft in an internal combustion engine. The sensors are used for feedback of the motor controller to the Powertrain Management Module. You can also use a crank sensor for measuring rotation speed. The most common design of the crank sensor is a torsion bar which is attached to the crankshaft.
- Hall Effect Sensor – is a device used in a variety of applications that monitor magnetic fields. In its most basic form, a Hall effect sensor consists of a permanent magnet and a special magnetoresistive (MR) sensor that is responsive to magnetic fields, much like the way a loudspeaker is responsive to audio signals. The magnetic field affects the MR sensor, and this, in turn, is detected by electronic circuitry. The output of the sensor is an analog voltage that is proportional to the strength of the magnetic field.
Checking a crank sensor with a multimeter is a simple test and a useful troubleshooting tool. This is a device that measures the position of the crank axle in a car’s engine. It is typically used in conjunction with other sensors to determine whether the engine is running incorrectly and to adjust the engine’s drive cycle during operation.
Replacing the Crank Sensor
Replacement crank sensors are expensive, and if you’re the DIY type, you’ve probably already learned to replace them yourself. The crank sensor is a small component connected to the engine block, and its job is to enable your car’s timing belt (or timing chain) to work properly. The most common symptom of a crank sensor malfunction is an engine that won’t turn over. If you’re having this problem, it’s important that you get your sensor replaced as soon as possible to avoid more serious engine damage.
Sometimes when you turn on your car, you hear a grinding or clicking sound. This sound is usually caused by a worn-out or faulty crank sensor in your engine. The crank sensor is a part of the ignition system that measures the rate of engine speed to make sure that the ignition coil is being supplied with the proper amount of current. To check the crank sensor, you need to use an automotive multimeter. If you are not familiar with using a multimeter, please consult a professional mechanic for assistance.