BMW Cars 1999-06

Camshaft Position Sensor

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Description & Operation



  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

  1. The static hall sensors are used on this sensor so that the camshaft positions are recognized once ignition is on and even before the engine is started.
  2.  
  3. There are four functions of the intake camshaft position sensor:

    Cylinder bank detection for preliminary injection
     
    Synchronization
     
    Engine speed sensor (if crankshaft speed sensor fails)
     
    Position control of the intake cam (VANOS)
     

  4.  
  5. The exhaust camshaft sensor is used for position control of the exhaust camshaft as part of the VANOS (variable camshaft control) system.
  6.  
  7. If these sensors fail, there will be no substitute values and the system will operate in the failsafe mode with no VANOS adjustment. The engine will still operate, but a significant reduction torque reduction will be quite noticeable.
    NOTE
    Use caution when removing or repairing the camshaft sensor and related mechanicals, as you should not want to bend the impulse wheels.

  8.  

Except M20 And S14 Engines

The Camshaft Position (CMP) sensor is used by the Engine Control Module (ECM) for the operation of the sequential fuel injection, ignition timing and knock (detonation) control.

The sensor mounts on the front or side of the cylinder head and uses a reference marker on the camshaft to collapse the field windings in the sensor to create an electrical pulse. The ECM uses this electrical pulse to identify when cylinder No. 1 is at Top Dead Center (TDC) of it's firing stroke.

This signal is used by the engine to determine when to create an ignition spark as well as actuate the fuel injector for each cylinder. The engine's firing order is programmed into the ECM, therefore the ECM only needs to recognize the position of cylinder No. 1.

If the CMP fails, no ignition spark will occur and the fuel injectors will not be actuated.



Click image to see an enlarged view

Fig. The Camshaft Position (CMP) sensor is located on the front housing of the cylinder head on M42 and M44 engines



Click image to see an enlarged view

Fig. The reference marker mounted on the camshaft creates an electrical pulse when it passes by the Camshaft Position (CMP) sensor. Note the camshaft timing marks, cylinder No. 1 is at TDC

Removal & Installation




CAUTION
Make sure that the ignition is switched off and no electrical equipment is on or running.

  1. For cars equipped with an acoustic cover that is screwed down, remove the seal caps and unfasten the nuts.
  2.  
  3. For cars equipped with an acoustic cover that is held in place with press stud fasteners, open the press-studs one at a time, while lifting the acoustic cover slightly on all four corners. Once all four press-studs have been opened, remove the acoustic cover.
  4.  
  5. Disconnect the plug-in electrical connection (3).

    Click image to see an enlarged view

    Fig. Disconnect the plug-in electrical connection (3)

  6.  
  7. To remove the sensor, unscrew the screw and pull out the sensor.

    Click image to see an enlarged view

    Fig. Unscrew the screw and pull out the sensor

  8.  

To install:

  1. Make sure to check the seal for damage and replace it if necessary.
  2.  
  3. Make sure to replace the line routing in the same manner it was removed, by following the original route and securing it with a cable connector.
  4.  
  5. Reposition the acoustic cover and press downwards until the four press-studs fasteners click audibly into place.
  6.  
  7. Access the fault memory of control unit of Digital Motor Electronics (DME), check for any stored fault messages, rectify those faults and clear the fault memory.

    Click image to see an enlarged view

    Fig. Remember to follow the original placement of the line (dark color cable in the photo)

  8.  


CAUTION
Make sure that the ignition is switched off and no electrical equipment is on or running.

  1. For cars equipped with an acoustic cover that is screwed down, remove the seal caps and unfasten the nuts.
  2.  
  3. For cars equipped with an acoustic cover that is held in place with press stud fasteners, open the press-studs one at a time, while lifting the acoustic cover slightly on all four corners. Once all four press-studs have been opened, remove the acoustic cover.
  4.  
  5. Disconnect the plug-in electrical connection (3).

    Click image to see an enlarged view

    Fig. Disconnect the plug-in electrical connection (3)

  6.  
  7. To remove the sensor, unscrew the screw and pull out the sensor.

    Click image to see an enlarged view

    Fig. Unscrew the screw and pull out the sensor

  8.  

To install:

  1. Make sure to check the seal for damage and replace it if necessary.
  2.  
  3. Make sure to replace the line routing in the same manner it was removed, by following the original route and securing it with a cable connector.
  4.  
  5. Reposition the acoustic cover and press downwards until the four press-studs fasteners click audibly into place.
  6.  
  7. Access the fault memory of control unit of Digital Motor Electronics (DME), check for any stored fault messages, rectify those faults and clear the fault memory.

    Click image to see an enlarged view

    Fig. Remember to follow the original placement of the line (dark color cable in the photo)

  8.  


CAUTION
Make sure that the ignition is switched off and no electrical equipment is on or running.

  1. Access the fault memory of control unit of Digital Motor Electronics (DME), check for any stored fault messages, rectify those faults and clear the fault memory.
  2.  
  3. Remove distributor cap with left ignition wiring harness,
  4.  
  5. Unscrew the bolt that retains the sensor (1) and remove the unit.

    Click image to see an enlarged view

    Fig. The location of the bolt (1) that connects the camshaft position sensor to the engine block

  6.  

To install:

  1. Check the seal of the sensor for damage and replace it if necessary.
  2.  
  3. To facilitate assembly coat seal with anti-friction agent.

    Click image to see an enlarged view

    Fig. Check the seal of the sensor (1) for damage and replace it if necessary

  4.  


CAUTION
Make sure that the ignition is switched off and no electrical equipment is on or running.

  1. For cars equipped with an acoustic cover that is screwed down, remove the seal caps and unfasten the nuts.
  2.  
  3. For cars equipped with an acoustic cover that is held in place with press stud fasteners, open the press-studs one at a time, while lifting the acoustic cover slightly on all four corners. Once all four press-studs have been opened, remove the acoustic cover.
  4.  
  5. Disconnect the plug-in electrical connection (3).

    Click image to see an enlarged view

    Fig. Disconnect the plug-in electrical connection (3)

  6.  
  7. To remove the sensor, unscrew the screw and pull out the sensor.

    Click image to see an enlarged view

    Fig. Unscrew the screw and pull out the sensor

  8.  

To install:

  1. Make sure to check the seal for damage and replace it if necessary.
  2.  
  3. Make sure to replace the line routing in the same manner it was removed, by following the original route and securing it with a cable connector.
  4.  
  5. Reposition the acoustic cover and press downwards until the four press-studs fasteners click audibly into place.
  6.  
  7. Access the fault memory of control unit of Digital Motor Electronics (DME), check for any stored fault messages, rectify those faults and clear the fault memory.

    Click image to see an enlarged view

    Fig. Remember to follow the original placement of the line (dark color cable in the photo)

  8.  

M42, M44 And M50 Engines
  1. The ignition switch must be in the OFF position.
  2.  
  3. The cylinder identifying connector is mounted on the timing cover with a bolt.
  4.  
  5. Remove the bolt and pull the sensor out of the timing cover.
  6.  
  7. Unplug the connector at the mounting bracket.
  8.  

To install:

  1. Check the O-ring around the sensor and install in the timing cover.
  2.  
  3. Tighten the mounting bolt to 4.5-5.5 ft. lbs. (6-8 Nm).
  4.  
  5. Plug in the connector and route the wire.
  6.  

S50, M52 And S52 Engines

NOTE
When installing a new sensor, make sure the wiring is properly routed. Secure the sensor wiring with new zip ties.

  1. Remove the plastic trim cover from above fuel injectors.
  2.  
  3. Detach the electrical connector from the VANOS solenoid.
  4.  
  5. Unscrew the solenoid from VANOS control unit by turning it counterclockwise.
  6.  
  7. Remove the banjo bolt from the oil supply line at the VANOS control unit.
  8.  
  9. Remove CMP sensor fastener and the sensor from the left front of cylinder head, near the top of the oil filter housing.
  10.  
  11. Detach the CMP sensor electrical connector under the intake manifold.
  12.  
  13. Installation is in reverse order of removal making sure to use new O-rings and seals from the removed components.
  14.  
  15. Torque all components as follows:

    CMP sensor to cylinder head: 44 inch lbs. (5 Nm)
     
    VANOS oil supply banjo bolt: 23.6 ft. lbs. (32 Nm)
     
    VANOS solenoid: 22 ft. lbs. (30 Nm)
     

  16.  

Testing



Use a BMW service tester, the OBD I blink code or on OBD II vehicles, use a suitable Data Scan Tool (DST) to check for faults and/or if capable, to read the values of the components. If this diagnostic equipment is not available, proceed as follows.


WARNING
When checking component values (volts or ohms) a suitable digital volt/ohmmeter must be used otherwise the circuit and/or component may be damaged.

Except M20 And S14 Engines


Click image to see an enlarged view

Fig. Cylinder identifying and engine speed sensor pinouts



Click image to see an enlarged view

Fig. The upper connector is for the cylinder identifying sender and the lower is for the speed sensor-M42 engine shown, M50 has similar arrangement

The Camshaft Position (CMP) sensor is located on the cylinder head. On models without VANOS, it is located on the front timing cover above the water pump. On models with VANOS, the sensor is on the front left side of the cylinder head. The connector is located below the intake manifold, towards the front of the engine.

  1. Turn the ignition switch to the OFF position.
  2.  
  3. Trace the sensor lead back to the connector and disconnect.
  4.  
  5. Using a digital ohmmeter, check the resistance between terminals 1 and 2. The resistance should be 1.15-1.41 kilo-ohms.
  6.  

 
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