Troubleshooting a car's ignition system often begins with checking the crankshaft position sensor (CPS). For owners Nissan Sunny generation FB15 equipped with HR series engines, this procedure becomes critical if starting problems occur. If the engine stalls while driving or does not start at all, the problem may lie in this small but vital component.
Many car owners get lost trying to find this element under the hood, since it is hidden from direct view and is located in a hard-to-reach place. On the Nissan Sunny FB15, the sensor is located at the bottom of the engine, closer to the flywheel, which requires removal of the protective covers for visual inspection. Understanding the exact location and the ability to recognize it from photographs will save you time and money on diagnostics in the service.
In this article we will look in detail at how to find the sensor yourself, what tools you will need to check and replace it, and also look at the main symptoms of failure. We will also provide information to help you distinguish the original part from a low-quality copy.
Design features and location of the sensor
Engine crankshaft position sensor HR12DE or HR15DE (depending on the configuration) plays the role of the main synchronizer of engine operation. It reads the teeth of the crankshaft pulley and transmits a signal to the electronic control unit (ECU). Without this signal, the engine management system cannot determine the moment of fuel injection and spark formation.
The element is physically mounted on the gearbox housing or cylinder block, in close proximity to the crankshaft damper. It is covered on top by a plastic engine protective cover and various hoses of the crankcase ventilation system. To get to it, it is often necessary to remove the plastic cover of the engine compartment.
It is important to consider that on some modifications Nissan Sunny access to the sensor may be partially blocked by the generator or drive belts. Therefore, before starting work, it is necessary to evaluate the layout of your specific instance. Sometimes it is necessary to move the wiring harnesses aside to gain visual contact with the sensor body.
Symptoms and diagnostics
A failure of the crankshaft sensor results in an immediate engine stop or inability to start. The ECU simply does not see the crankshaft speed and blocks the operation of the injectors and ignition coils. This is a protective measure to prevent flooding of the spark plugs and overheating of the catalyst with unburnt fuel.
The main symptoms include:
- 🚗 The engine starts with great difficulty, but after several attempts it starts and runs stably.
- 🚗 Sudden engine stop while driving without warning, even on a warm engine.
- 🚗 The presence of error P0335 in the OBD-II diagnostic system, indicating the absence of a signal from the sensor.
- 🚗 Floating idle speed and dips when pressing the gas.
Often the problem lies not in the sensor itself, but in a break in its wiring or oxidation of the connector contacts. Engine vibrations can loosen the wires over time. Before purchasing a new spare part, be sure to check the integrity of the insulation and the reliability of the chip’s fixation.
⚠️ Attention: Do not try to start the engine multiple times in a row if you suspect a faulty DPKV. This can lead to battery discharge and spark plugs flooding with gasoline, which will complicate further diagnostics.
- Yes, the engine did not start the first time
- Yes, the car stalled while driving
- No, everything works fine
- Haven't checked yet
Step-by-step instructions for searching and dismantling
To begin work, it is necessary to provide access to the engine. Remove the plastic decorative cover of the engine compartment by unfastening the plastic clips. Next, if space allows, unscrew and move the air filter or intake system elements to the side to better see the sensor mounting area.
Find the sensor based on the photo in the manual or the description: it will be located at the bottom of the engine, at the end of the cylinder block, near the junction with the gearbox. The sensor housing is usually black, with a plastic connector from which the wiring harness extends.
The dismantling process requires caution, since the mounting bolt may be soured. Use a suitable socket to avoid stripping threads. Disconnect the electrical connector by pressing the latch and carefully remove the sensor itself from its seat.
☑️ Preparing to remove the sensor
When removing, pay attention to the gap between the sensor and the pulley. If there is heavy contamination or oil stains on the sensing element, this may cause false alarms. Cleaning may temporarily solve the problem, but if the sensor is internally defective, replacement is inevitable.
Features of bolt fastening
The sensor mounting bolt often has a special gasket that must not be lost. If the gasket is lost or damaged, the clearance may change, causing the engine to not run properly. It is recommended to immediately purchase a new gasket complete with the sensor.
Technical characteristics and selection of spare parts
When choosing a replacement for Nissan Sunny FB15 It is important to consider the type of sensor. Most HR series motors use inductive sensors that operate on the principle of electromagnetic induction. They do not require external power, but are sensitive to contamination.
There are several manufacturers whose products are suitable for replacement. The original will always be the most reliable option, but there are high-quality analogues from trusted brands. The main thing is to make sure that the article number and the number of contacts in the connector match.
Below is a table with common articles and manufacturers:
| Manufacturer | Original number | Analogues | Features |
|---|---|---|---|
| Nissan (OEM) | 23731-1EA0A | 23731-1EA0B | Maximum reliability, high price |
| Denso | DPC-1001 | DPC-1002 | Quality supplier for the conveyor |
| NTK (NGK) | 73510 | 73511 | Good value for money |
| Stanley | 0224-0001 | 0224-0002 | Budget option, requires verification |
Before installing a new part, be sure to clean the seat from dirt and oil. Install a new gasket if included. This ensures that the correct clearance is maintained and prevents technical fluids from entering the housing.
⚠️ Attention: Do not use sealant instead of the standard gasket when installing the sensor. This may change the clearance and cause unstable engine operation or damage to the sensing element.
Before purchasing a sensor, check the markings on the old element. Sometimes the batch number or production date is stamped on the case, which will help you find an exact analogue in supplier catalogs.
Multimeter check and installation
To verify that the sensor is faulty, you can test it with a multimeter. Set the device to resistance measurement mode (Ohms). Connect the probes to the sensor contacts. The normal resistance value for most Nissan inductive sensors is between 500 and 1500 ohms.
Also check the circuit for open circuit and short circuit to body. If the resistance is infinitely high (open) or close to zero (short), the sensor is faulty. Additionally, check the insulation of the wires going to the connector.
Installing a new sensor is done in the reverse order. After installation, do not forget to connect the electrical connector until you hear a characteristic click. Start the engine and make sure that the error disappears and the engine is running smoothly.
Correct installation of the crankshaft sensor is critical: even a slight misalignment can lead to an incorrect signal and engine shutdown, so always use the stock gasket.
Frequent replacement errors and prevention
One of the most common mistakes is overtightening the mounting bolt. The plastic housing of the sensor can crack under excessive force, which will lead to its rapid failure. Tighten the bolt to the recommended torque, usually no more than 10 Nm.
Another problem is damage to the sensing element during cleaning. Do not use wire brushes or abrasives to clean the sensor end. A soft cloth and alcohol are the best choices for removing dirt and oil.
For prevention, it is recommended to regularly inspect the sensor wiring for insulation damage. Over time, engine vibrations can lead to chafing of the wires, especially in places where they are bent or attached to the body.
⚠️ Attention: If error P0335 does not disappear after replacing the sensor, the problem may be in the crankshaft pulley (teeth worn out) or in the ECU itself. In this case, professional diagnosis is necessary.
What to do if the sensor does not fit?
Sometimes it seems that the new sensor does not fit, but the problem is only a mismatch in the shape of the connector. In such cases, you can use an adapter or carefully re-crimp the contacts, observing the polarity. However, it is better to look for a part with an identical connector.
FAQ: Frequently asked questions
Where exactly is the crankshaft sensor located on the Nissan Sunny FB15?
The sensor is located at the bottom of the engine, on the cylinder block, on the gearbox side. To access it, you often need to remove the plastic engine protection and move the wiring harnesses aside.
Is it possible to start the engine without a crankshaft sensor?
No, without a signal from the sensor, the ECU does not know when to inject and spark, so the engine will not start. The exception is when the sensor is temporarily disabled, but this is not possible while the engine is running.
How much does it cost to replace a sensor at a service center?
The cost of working in the service usually ranges from 1,500 to 3,000 rubles, depending on the region and complexity of access. The sensor itself costs from 2000 to 6000 rubles.
How often should the crankshaft sensor be replaced?
The sensor does not have a replacement schedule and serves until it fails. The average service life is 100-150 thousand kilometers, but it can fail earlier due to overheating or mechanical damage.
What errors does the scanner show when there is a malfunction?
The main fault is P0335 (Crankshaft Position Sensor Circuit Malfunction). Errors associated with misfire or unstable speed may also appear.