How To Test The Camshaft Position Sensor (2000-2002 1.8L Nissan Sentra)

Testing the camshaft position sensor on the 2000-2002 1.8L Nissan Sentra is pretty easy. In this tutorial I'm gonna' show you how to using only a multimeter (no scan tool required).

With the results of this test, you'll be able to find out if the cam sensor is bad or not.

Here are the contents of this tutorial:

  1. Symptoms Of A Defective Camshaft Position Sensor.
  2. Circuit Descriptions Of The Camshaft Position Sensor.
  3. TEST 1: Checking The Camshaft Position Signal With A Multimeter.
  4. TEST 2: Making Sure The Cam Sensor Is Getting Power.
  5. TEST 3: Making Sure The Cam Sensor Is Getting Ground.
  6. Location Of The Camshaft Position Sensor.
  7. Where To Buy The Camshaft Position Sensor.
  8. More 1.8L Nissan Sentra Tutorials.

Symptoms Of A Defective Camshaft Position Sensor

Here is a basic list of the symptoms you are going to see when the camshaft position sensor fails on your 2003 2002 1.8 liter Nissan Sentra.

  1. A trouble code P0340: Camshaft Position Sensor A Circuit lighting up the check engine light.
  2. Car cranks but does not start.
  3. The fuel injection computer does not pulse activate the fuel injectors (this is verified with a noid light test).
  4. The fuel injection computer does not activate the ignition coils (this is verified with a spark tester).
  5. The fuel pump activates and sends the correct fuel pressure to the fuel injectors (this is verified with a fuel pressure gauge).

NOTE: You can find the location of the cam sensor here: Location Of The Camshaft Position Sensor.

Circuit Descriptions Of The Camshaft Position Sensor

How To Test The Camshaft Position Sensor (2000-2002 1.8L Nissan Sentra)

The camshaft position sensor on your 2000, 2001, or 2002 1.8L Nissan Sentra has 3 wires sticking out of its electrical connector.

In effect the camshaft position sensor, on the 2000-2002 1.8L Nissan Sentra is a Hall Effect sensor. This means that the sensor needs a power source and ground to be able to generate a signal.

So one of the three wires feeds the cam sensor with battery voltage. Another wire feed its chassis ground. And one wire is the one that transmits the cam position signal to the fuel injection computer.

Below you'll find a brief description of each circuit.

Cam Position Sensor (2000, 2001, 2002 1.8L Nissan Sentra)
Terminal Wire Description
1 BLK Ground
2 RED Camshaft Position Signal
3 WHT Power -12 Volts

TEST 1: Checking The Camshaft Position Signal With A Multimeter

Checking The Camshaft Position Signal With A Multimeter. How To Test The Camshaft Position Sensor (2000-2002 1.8L Nissan Sentra)

The camshaft position sensor on your Nissan Sentra is designed to produce and on off voltage as the engine turns. In layman's terms, this means that the signal voltage alternates between 10 volts and 0 volts the entire time the engine is running.

To get this show on the road the very first thing that we are going to do is connect the our multimeter to the signal wire of the camshaft sensor and then turn the engine by hand (that's right, we're not gonna use the starter motor).

If the cam sensor is OK, it will generate a voltage that will alternate between 10 Volts and 0 Volts (as we manually turn the engine).

If the cam sensor is bad, it'll stay stuck producing a voltage of about 10 volt and never drop to 0 Volts.

OK, let's get started:

  1. 1

    Raise the front passenger side of your Sentra onto a jack stand (for safety).

    Remove the front passenger side wheel and remove the plastic water splash guard (shield) that protects the crankshaft pulley and serpentine belt from water.

  2. 2

    Disconnect the cam sensor from its electrical connector. As a safety precaution, disconnect all of the ignition coils from their electrical connectors.

  3. 3

    Connect the red multimeter lead to the red wire of the camshaft position sensor's connector. You'll need to use a tool like a wire piercing probe to connect the red test lead to the red wire.

    You can see a what a wire piercing probe looks like here: Wire Piercing Probe.

  4. 4

    Connect the connector back to the camshaft position sensor. The camshaft position sensor must be connected to its electrical connector for this test to work.

  5. 5

    Set your multimeter to Volts DC mode and ground the black multimeter lead directly on the battery negative (-) terminal.

  6. 6

    Slowly turn the crankshaft pulley by hand in a clock-wise direction while you keep you eyes on the multimeter once you have the multimeter set up. Do not use the starter motor to crank the engine and I want to emphasize slowly turning the crank pulley.

  7. 7

    If the cam sensor is working correctly, the multimeter will register an On/Off voltage of 9-10 and 0 Volts DC as you manually turn the crankshaft. Off is when the multimeter displays 9.5 - 10 Volts DC and On is 0 Volts DC.

    To be a little more specific: your multimeter will register 9 to 10 volts most of the time you're turning the crank pulley. When the cam sensor is activated (and if it's working correctly) by the pole piece on the camshaft, then this voltage will go down to 0 Volts.

Let's take a look at what your test results mean:


CASE 1: The multimeter registered 9.5 to 10 Volts DC and the 0 Volt pulse as you manually turned the crankshaft pulley. This result indicates that the camshaft position sensor is working fine.

CASE 2: The multimeter DID NOT register the On/Off 9.5 to 10 Volts DC and 0 Volts pulse as you manually turned the crankshaft pulley. This result indicates that the camshaft position CMP sensor is not creating a signal.

The next step is to verify that it's getting power (12 volts). For this test, go to: TEST 2: Making Sure The Cam Sensor Is Getting Power.