TEST 1: Testing The Power Circuit For 12 Volts

How To Test The MAF Sensor (GM 4.8L, 5.3L, 6.0L, 8.1L)

OK, the very first thing that you'll need to do is to make sure the mass air flow (MAF) sensor is getting power (12 Volts). You can use a test light or a multimeter. The following test steps assume that you're using a multimeter.

By the way, I recommend that you test the circuit with the connector connected to the mass air flow (MAF) sensor and using a wire piercing probe (or any other apropriate tool) to pierce the wire (to get to the signal). Probing the front of the terminal, to get to the 12 Volt Signal, could lead to some major complications.

OK, nuff said, here's the test:

  1. 1

    Place the multimeter in Volts DC mode.

  2. 2

    Disconnect the MAF sensor from its connector.

  3. 3

    Connect the red multimeter test lead to the PINK wire identified with the number 4 (see photo above) using an appropriate tool.

  4. 4

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

  5. 5

    Turn the key to the ON position and observe the voltage value the multimeter registers.

  6. 6

    The multimeter should register between 10 to 12 Volts DC.

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

CASE 1: The multimeter registered 10 to 12 Volts DC. This is the correct test result and it indicates that the MAF sensor is getting juice (12 Volts).

The next step is to verify that it's also getting a good Ground, go to: TEST 2: Testing The Ground Circuit.

CASE 2: The multimeter DID NOT register 10 to 12 Volts DC. Without power the MAF sensor will not work.

This test result exonerates the MAF sensor itself as being bad. Repairing the cause of the missing voltage will solve the MAF sensor problem.

TEST 2: Testing The Ground Circuit

How To Test The MAF Sensor (GM 4.8L, 5.3L, 6.0L, 8.1L)

Testing the Ground circuit follows pretty much the same procedure as the test steps for testing the power circuit. Here are the steps:

  1. 1

    Place the multimeter in Volts DC mode.

  2. 2

    Disconnect the MAF sensor from its connector.

  3. 3

    Connect the black multimeter test lead to the black (or black with white stripe) wire identified with the number 3, in the photo above, using an appropriate tool.

  4. 4

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

  5. 5

    Turn the key to the ON position and observe the voltage value the multimeter registers.

  6. 6

    The multimeter should register between 10 to 12 Volts DC.

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

CASE 1: The multimeter registered 10 to 12 Volts DC. This is the correct test result and it indicates that the MAF sensor is getting Ground.

The next step is to verify that the MAF sensor is creating a good MAF Signal based on the airflow the engine is breathing, go to: TEST 3: Testing The MAF Signal Circuit.

CASE 2: The multimeter DID NOT register 10 to 12 Volts DC. Without Ground the MAF sensor will not function.

This test result exonerates the MAF sensor itself as being bad. Repairing the cause of the missing Ground will solve the problem.

Buick Vehicles:
  • Rainier 5.3L
    • 2004, 2005, 2006, 2007
Cadillac Vehicles:
  • Deville
    • 2001, 2002, 2003, 2004, 2005
  • Eldorado
    • 2000, 2001, 2002
  • Escalade
    • 2002, 2003
Cadillac Vehicles:
  • Seville
    • 2000, 2001, 2002, 2003
Chevrolet Vehicles:
  • Avalanche 5.3L, 8.1L
    • 2002, 2003, 2004, 2005
  • Silverado (1500, 2500, 3500)
    • 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
Chevrolet Vehicles:
  • Suburban (1500, 2500)
    • 2000, 2001, 2002, 2003, 2004, 2005
  • Tahoe 4.8L, 5.3L
    • 2000, 2001, 2002, 2003, 2004, 2005, 2006
  • TrailBlazer 5.3L
    • 2003, 2004
GMC Vehicles:
  • Envoy 5.3L
    • 2003, 2004
  • Sierra (1500, 2500, 3500)
    • 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
  • Yukon 4.8L, 5.3L
    • 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
Hummer Vehicles:
  • H2 6.0L
    • 2003, 2004, 2005
Isuzu Vehicles:
  • Ascender 5.3L
    • 2003, 2004, 2005, 2006