The 3 Wire Crank Sensor Wiring Diagram is a type of sensor that is commonly found in modern vehicles. This sensor operates by noticing differences in the magnetic flux of an object when it comes around the sensor.
It then creates an electrical voltage, which is sent to the ECU to help control the fuel injection or ignition system timing and other engine parameters. The 3-wire crank sensor wiring diagram can be quite complex, with three wires including a reference voltage wire, signal wire, and ground wire, all of which are connected to the ECU.
Comprehending the wiring diagram of the 3-wire crank sensor can assist you to troubleshoot any problems related to your vehicle’s crankshaft position sensor and assure that your engine is operating smoothly.
3 Wire Crank Sensor Wiring Diagram

A crankshaft position sensor is an electronic appliance that defines the place of the crankshaft. There are two primary types of crankshaft position sensors commonly used in vehicles.
The first type is the inductive coil pick-up crank sensor, which induces an alternating current in the coil. The second type is the Hall-effect crank sensor, which creates a digital square wave signal and transfers it to the car’s ECU. Most modern cars employ Hall-effect crankshaft sensors due to their raised accuracy. Inductive pick-up coil sensors have two wires, while Hall-effect sensors have three wires.
We will discuss the wiring diagrams for 2 and 3-wire crank sensors in this complete guide.
What is Crankshaft Position Sensor?
A Crankshaft Position Sensor (CKP) is an electronic part utilized in internal combustion engines, including both petrol and diesel engines, to check the status and rotational speed of the crankshaft. Engine management systems utilize this information to regulate fuel injection, ignition system timing, and other engine parameters.
The crankshaft sensor registers the engine’s rotational speed (RPM) and the exact position of the engine crankshaft. The fuel injection system depends on the crank position sensor to synchronize the fuel injectors, while the sensor also monitors the engine’s speed.
Crankshaft Position Sensor
Crankshaft sensor electrical diagrams vary depending on the vehicle’s make, model, and year. Manufacturers create electrical schematics for the crank position sensor based on specific requirements and demands.
In this guide, we will provide a general understanding of how crank position sensor wiring is designed. For information specific to your vehicle, consult your car’s owner’s manual.
Wire colors may vary and are color-coded based on the sensor’s brand. The following are electrical schematics for two and three-wire crank position sensors.
2 Wire Crank Sensor Wiring Diagram
A two-wire crankshaft position sensor circuit has two wires:
- Signal Wire
- Ground
The two-wire crank position sensor sends its voltage to the ECU through a signal wire. A ground wire is required to complete an electrical circuit and is connected to the electronic control unit.
A two-wire crankshaft sensor is an inductive type, consisting of a sensor magnet and coil. As the crankshaft’s reluctor ring approaches the crank sensor, voltage is generated and sent to the car’s computer.
The inductive-type crank position sensor, also known as a magnetic pick-up sensor, has two wires: an earth wire and a signal (voltage) wire.
Inductive-type crankshaft position sensors have two wires because they contain a coil (and magnet) that produces its magnetic flux and voltage in the coil when the crankshaft reluctor ring comes closer. It does not require an external positive voltage source wire for activation.
The sensor generates a signal (output voltage created by the crankshaft sensor) that is transmitted to the electronic control unit without supplying a positive current. This is why inductive-type crankshaft position sensors have two wires. A two-wire sensor is an inductive type sensor.
3 Wire Crank Sensor Wiring Diagram
The three-wire crankshaft sensor has three wires as follows:
- Reference Voltage Wire
- Signal Wire
- Ground
All of these wires are connected to the electronic control unit. A 3-wire crankshaft sensor receives a power source called reference voltage from the ECU. The sensor’s ground is also connected to the ECU, and the signal voltage wire extends from the sensor to the computer.
A three-wire sensor is typically a Hall-effect type sensor, which consists of a magnet, a steel-type material like germanium, and a transistor. When an object comes close to the sensor, its magnetic flux changes, leading to voltage production in the material. This voltage is then boosted by the transistor and sent to the electronic control unit (ECU).
The Hall-effect sensor requires an external voltage source for its integrated electronics (transistors) to function properly.
They are normally provided with a 5-volt power source, but in some cases, it can be 12 volts. These sensors contain three wires: one for voltage, the second for ground, and a third signal wire (which links the sensor to the ECU).
The respect voltage is the voltage supplied by the ECU to the sensor, while the signal voltage is the voltage transmitted from the sensor to the car’s computer (ECU). Since the voltage induced by the Hall-effect sensor is minimal, an amplifier circuit (transistor) is incorporated into the sensor to promote the voltage.
Difference Between Hall Effect and Inductive Type Crank Sensor
The primary distinction between these two types of sensors lies in their operation and wiring. The Hall-effect crankshaft sensor requires external voltage for its integrated circuit to function, as it contains a built-in amplifier to boost the voltage.
Therefore, it has three wires: earth, voltage, and signal wire. The inductive-type crankshaft sensor, on the other hand, does not require external voltage, as it generates its own voltage when an object approaches it. It has only two wires: earth and signal wire.
In summary, the inductive coil pick-up crank sensor generates an alternating current and typically has two wires, while the Hall-effect crank sensor produces a digital square wave signal and usually has three wires. The Hall-effect sensor is more commonly used in modern vehicles due to its superior accuracy.
To determine the appropriate wiring diagram for your specific vehicle’s crank position sensor, consult your car’s owner manual. It is important to note that wire colors may differ and are color-coded according to the sensor brand.
Understanding the differences between two and three-wire crank position sensors, as well as their respective wiring diagrams, will help you troubleshoot any issues related to your vehicle’s crankshaft position sensor.
Frequently Asked Questions:
- What are the three wires on a crankshaft sensor?
The three wires on the crankshaft position sensor are the Reference Voltage Wire, Signal Wire, and Ground Wire. These wires are all connected to the ECU.
- How much resistance should a crankshaft sensor have?
A properly functioning crankshaft sensor typically has a resistance of 200Ω to 2000Ω. If the resistance is zero ohms, it indicates a short circuit. The amount of resistance a crankshaft sensor should have relies on many elements, such as the type and age of the engine, as well as the operating conditions. In general, newer engines have sensors with less resistance than older engines, and engines operating in harsher conditions will have sensors with less resistance.
- How does a 3-wire crankshaft sensor work?
A 3-wire crankshaft sensor, typically a Hall-effect type sensor, uses a magnet and a steel-type substance called germanium, along with a transistor. It detects changes in the magnetic flux of an object when it comes near the sensor, which creates an electrical voltage that is sent to the ECU.
- What sensors can cause a crank to no-start?
A crank no-start can be induced by a combination of sensors, such as the crankshaft position sensor, throttle position sensor, coolant sensor, and fuel pump. These sensors can fail or have their wiring damaged, which can result in the engine either stalling or not starting at all.
In some cases, the engine may crank but not start, indicating that the issue is likely not related to the battery, cables, or starter motor. Other possible causes include a bad fuel pump or a clogged fuel filter. In some cases, a lack of timing signal from the crankshaft position sensor to the ECU may also be the cause.
- How do you test a 3-pin crank sensor?
To test a 3-pin crankshaft sensor, you will need a multimeter set to DC voltage. First, identify the power, ground, and signal wires using your vehicle’s manual. Then, unplug the crankshaft position sensor and link one multimeter directing to one of the sensor’s pins and the other leading to another pin.
Finally, take readings from the signal, reference, and ground wires and compare them to the indications contained in the car manual. If the readings are not even, the crankshaft sensor is probably defective.
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Conclusion:
Understanding the wiring diagram of the 3 wire crank sensor wiring diagram is crucial for proper engine functioning.
The crankshaft position sensor is a vital component of a vehicle’s engine management system, and any issues with the sensor’s wiring can cause significant problems.
By knowing the wiring diagram, you can troubleshoot any issues with the sensor, whether it’s a faulty sensor or wiring damage. It’s also important to keep in mind that wire colors may vary depending on the sensor brand and the vehicle’s make and model.
By consulting your car manual, you can ensure that you have the correct wiring diagram for your specific vehicle’s crankshaft position sensor.
Ultimately, understanding the 3-wire crank sensor wiring diagram is an essential step in maintaining the health and longevity of your vehicle’s engine.