TEST 1: Testing The MAF's Power (12 V) Circuit

Making Sure The MAF Sensor Is Getting Power. Mass Air Flow (MAF) Sensor Test 3.5L Nissan Maxima (2001-2003)

The first thing we're gonna' do is make sure that the MAF sensor is getting battery power.

This battery power come's from your Maxima's ECM power relay and is fed to the MAF sensor thru' the red with green stripe (RED/GRN) wire of the harness connector.

This RED/GRN wire is labeled with the number 4 in the photo above.

OK, these are the test steps:

  1. 1

    Place your trusty multimeter in VOLTS DC mode.

  2. 2

    Probe the MAF sensor wire, that's identified with the number 4 in the photo, with the red multimeter test lead.

  3. 3

    Connect the black test lead of the multimeter to the battery (-) negative terminal.

  4. 4

    Turn Key On but don't crank or start the engine. This will power up the fuel injection system.

  5. 5

    Your multimeter should read 10 to 12 Volts DC if power is available at the RED/GRN wire.

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

CASE 1: Your multimeter registered 10 to 12 Volts. This result indicates that the Maxima's MAF sensor is getting juice (power). The next step is to test the Ground circuit, go to TEST 2.

CASE 2: Your multimeter DID NOT register 10 to 12 Volts. Recheck all of your multimeter connections and retest. If still no voltage, then this result exonerates the Maxima's MAF sensor as the cause of the MAF code or MAF issue, since without this voltage, the MAF sensor will not produce a signal to the computer.

Finding and repairing the source of this missing voltage will resolve the MAF sensor issue with your Nissan Maxima.

TEST 2: Testing The MAF's Ground Circuit

Making Sure The MAF Sensor Is Getting Ground. Mass Air Flow (MAF) Sensor Test 3.5L Nissan Maxima (2001-2003)

In this test section, we're gonna' make sure that the black (BLK wire of the MAF sensor harness connector is feeding the MAF sensor with Ground.

The BLK wire is labeled with the number 3 in the photo above.

IMPORTANT: Be careful not to short this wire to battery power or you'll fry your Maxima's fuel injection computer. The multimeter voltage test indicated below is a safe way to test this Ground circuit.

Alright, let's get started:

  1. 1

    Turn key to the ON Position but don't crank or start the engine.

    Place your trusty multimeter in VOLTS DC mode.

  2. 2

    Test the BLK wire identified with the number 3 in the photo above with the black multimeter test lead.

  3. 3

    Connect red multimeter test lead to the battery positive (+) terminal.

  4. 4

    Your multimeter should register 10 to 12 Volts if Ground is available in the BLK wire.

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

CASE 1: Your multimeter registered 10 to 12 Volts. This result indicates that the Maxima's MAF sensor has a good Ground circuit. The next step is to test the MAF signal, go to TEST 3.

CASE 2: Your multimeter DID NOT register 10 to 12 Volts. Recheck all of your multimeter connections and try the test again. If still no voltage, then this result exonerates the Maxima's MAF sensor as the cause of the MAF code lighting up your check engine light (CEL) or MAF issue, since without this Ground, the MAF sensor will not produce a signal to the computer.

Finding and repairing the cause of this missing Ground will resolve the MAF sensor issue with your Nissan Maxima.