Sentra 2007

Camshaft Position Sensor

Print

Location



2.0L Engine

Specific to:

Nissan Sentra 2007-2012



Click image to see an enlarged view

Fig. The Camshaft Position (CMP) sensor is on top of the engine near the ignition coil.

2.5L Engine

Specific to:

Nissan Sentra 2007-2012



Click image to see an enlarged view

Fig. The cam position sensor is located on top of the engine at the flywheel end.

Operation



Specific to:

Nissan Sentra 2007-2012

The Camshaft Position (CMP) sensor (PHASE) senses the rotation and position of the camshaft to identify the position of each piston. If the Crankshaft Position (CKP) sensor (POS) becomes inoperative, the Camshaft Position (CMP) sensor (PHASE) takes over various controls utilizing timing of cylinder identification signals. The sensor consists of a permanent magnet and Hall IC. When the engine is running, the high and low parts of the teeth cause the gap with the sensor to change. The changing gap causes the magnetic field near the sensor to change. Due to the changing magnetic field, the voltage from the sensor changes. The ECM receives the signals as shown in the figure.

Click image to see an enlarged view

Fig. Camshaft Position (CMP) sensor signal schematic

Removal & Installation



Specific to:

Nissan Sentra 2007-2012

  1. Unplug the connector.
  2.  
  3. Remove the bolt to remove the sensor.
  4.  
  5. During installation, use a new O-ring and make sure the sensor is clean and free of metal filings on the magnet end.
  6.  

Testing



CMP Circuit Testing

Specific to:

Nissan Sentra 2007-2012

Use a suitable scan tool or a graphing multi-meter (GMM) in order to view the CMP data.  

CMP sensor logic is based on alternating lines of magnetic flux which generate a digital on/off signal to the PCM, and are based on the speed and position of the camshaft.

Verify that the engine timing components (timing belt, timing chain, or timing gears) are properly installed, and that there is no foreign material obstructing the path between the reluctor and the CMP sensor. If any engine mechanical faults are evident, locate and repair as required before continuing.  

A digital volt-ohm meter (DVOM) may be used to verify the condition of the wiring: additional information may be acquired by taking measurements at the sensor connector as well as the PCM connector. If significant resistance is measured (greater than 5 ohms) is measured, check the wiring harness and connections for corrosion, poor pin connections, or damaged wires.

If all engine wiring and pin connections are confirmed, disconnect the CMP sensor to verify the signal with a GMM, and verify PCM communication before replacing the CMP sensor.

Click image to see an enlarged view

Fig. CMP Sensor Range Chart

CMP Sensor Strategy

Specific to:

Nissan Sentra 2007-2012

The CMP sensor provides a digital input signal to the powertrain control module (PCM) for a number of engine control system calculations. The CMP signal is compared with the Crankshaft Position (CKP) sensor (CKP) and vehicle speed sensor (VSS) for measured operating conditions, and the pulse width modulation pattern is used by the powertrain control module (PCM) to calculate ignition timing, firing order, fuel injector timing, and misfire diagnostics.

CMP sensor feedback patterns vary according to the reluctor configuration and PCM logic. While most models use a single tooth for top dead center (TDC), others may use multiple reluctor teeth for additional positions of camshaft rotation, which may include one per cylinder, or 0°,90°, 180°, and 270°respectively.

Connection & Wiring Diagnosis

Specific to:

Nissan Sentra 2007-2012

Refer to the electrical wiring diagram for component and connector locations, connector views, and circuit-specific information.  

Many intermittent open or short circuits may be caused by wiring harness and connector movement due to vibration, engine torque, bumps and rough pavement, etc.

  1. Test the wiring harness and connectors by performing the following tests:

    Move the related connectors and wiring while monitoring the appropriate scan tool data.
     
    Move the related connectors and wiring with the component commanded on and off. Using a suitable the scan tool, observe the component operation.
     
    With the engine running, move the related connectors and wiring while monitoring component operation.
     
    If harness or connector movement affects the data displayed, the component and system operation, or the engine operation, inspect and repair the harness or connections as necessary.
     

  2.  
  3. Test the connector terminal pins and/or wiring by performing the following tests:

    Inspect for incorrect mating of the connector halves, or terminals not fully seated in the connector Body.
     
    Inspect for improperly formed or damaged terminals and test for incorrect terminal tension.
     
    Inspect for poor terminal to wire connections including terminals crimped over insulation. This requires removing the terminal from the connector body.
     
    Inspect for corrosion or water intrusion. Pierced or damaged insulation can allow moisture to enter the wiring. The conductor can corrode inside the insulation with little visible evidence. Look for swollen and/or brittle sections of wire in the suspect circuits.
     
    Inspect for wires that are broken inside the insulation by gently pulling on suspect sections of wiring.
     

  4.  

Related Diagnostic Trouble Codes

Specific to:

Nissan Sentra 2007-2012



Click image to see an enlarged view

Fig. Related Diagnostic Trouble Codes

 
label.common.footer.alt.autozoneLogo