Component Inspection

1. Turn ignition switch OFF.
2. Start engine and warm it up to normal operating temperature.
3. Turn ignition switch OFF, wait at least 5 seconds and then turn ON.
4. Check the voltage between ECM harness connector terminals as follows.
   ECM HARNESS CONNECTOR TERMINALS REFERENCE CHART
   
   

   ECM
   +		-
   Connector	Terminal	Connector	Terminal
   F101	38	F102	96

   NOTE:

   • To avoid the influence of intake manifold vacuum, check the voltage 1 or more minutes past after engine is stopped.
   • Because the sensor is absolute pressure sensor, output value may differ depending on atmospheric pressure and altitude.
5. Measure the atmospheric pressure.
   NOTE: As the atmospheric pressure described on the synoptic chart is the value at sea level, compensate the pressure with the following chart.
   COMPENSATED PRESSURE SPECIFICATION
   
   

   Altitude	Compensated pressure
   0m	0hPa
   200m	-24hPa
   400m	-47hPa
   600m	-70hPa
   800m	-92hPa
   1000m	-114hPa
   1500m	-168hPa
   2000m	-218hPa

6. Check the manifold absolute pressure sensor value corresponding to the atmospheric pressure.
   TERMINALS VOLTAGE REFERENCE
   
   

   Atmospheric pressure	Voltage
   800hPa	3.1 - 3.7V
   850hPa	3.3 - 3.9V
   900hPa	3.5 - 4.1V
   950hPa	3.8 - 4.3V
   1000hPa	4.0 - 4.6V
   1050hPa	4.2 - 4.8V

   Fig 1: Manifold Absolute Pressure Valve Voltage Graph

   Courtesy of NISSAN MOTOR CO., U.S.A.

Is the inspection result normal? 

YES: GO TO 2.

NO: Replace MAP sensor.

1. Start engine and let it idle.
2. Check intake manifold vacuum.
3. Check the voltage between ECM harness connector terminals as follows.
   ECM HARNESS CONNECTOR TERMINALS REFERENCE CHART
   
   

   ECM
   +		-
   Connector	Terminal	Connector	Terminal
   F101	38	F102	96

4. Confirm the difference of the voltage when engine is stopped and at idling is within the values shown in the following chart.
   VOLTAGE REFERENCE CHART
   
   

   Intake manifold vacuum	Voltage difference
   -40kPa (-300mmHg)	1.5 - 2.0V
   -53.3kPa (-400mmHg)	2.0 - 2.6V
   -66.7kPa (-500mmHg)	2.6 - 3.2V
   -80kPa (-600mmHg)	3.2 - 3.8V

Is the inspection result normal? 

YES: INSPECTION END

NO: Replace MAP sensor.