MAF TEST 1: Testing The Power Circuit

Making Sure The MAF Sensor Is Getting Power. How To Test The Ford Mass Air Flow (MAF) Sensor

OK, to get this show on the road and find out if the MAF sensor on your Ford is bad, we'll test for power first.

I'm gonna' make you a very important recommendation: Don't test the front of the connector to test for this voltage.

What I suggest you to do is to use a test probe that pierces thru' the wire's insulation (Wire Piercing Probe). Avoid inserting anything into the female terminal.

Whatever method you use, the key here is to avoid damaging the MAF connector's female terminal or the wire. OK, this is what you need to do:

  1. 1

    Put the multimeter in VOLTS DC mode. Do not disconnect MAF sensor connector from the MAF sensor.

  2. 2

    With the red multimeter test lead and an appropriate tool, probe the MAF sensor connector's A circuit as shown in the photo.

  3. 3

    With the black multimeter test lead probe the battery negative (-) terminal. Turn Key On with the engine Off.

  4. 4

    You should see 12 Volts on the multimeter. Do you have 12 Volts?

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

CASE 1: Your multimeter registered 12 Volts. This is the correct result, the next step is to make sure the MAF sensor has Ground, for this, go to: MAF TEST 2: Testing The Ground Circuit.

CASE 2: Your multimeter DID NOT register 12 Volts. Recheck all of your multimeter connections and retest. If you still do not see these 12 Volts, then this exonerates the MAF sensor as bad since without this voltage it's not gonna' work.

MAF TEST 2: Testing The Ground Circuit

Making Sure The MAF Sensor Is Getting Ground. How To Test The Ford Mass Air Flow (MAF) Sensor

So far we know that the MAF sensor is getting juice (12 Volts). Let's find out if it's getting Ground too.

The Ford MAF sensor uses two different Ground paths, this one (that you're about to test) is just a chassis Ground and it connects directly on the engine or battery negative terminal.

Alright, this is what you need to do:

  1. 1

    Put the multimeter in VOLTS DC mode.

  2. 2

    With the black multimeter test lead and an appropriate tool, probe the wire identified with the letter letter B in the photo.

  3. 3

    With the red multimeter test lead probe the battery positive terminal.

  4. 4

    You should see 12 Volts on the multimeter. Do you have 12 Volts?

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

CASE 1: Your multimeter registered 12 Volts. This is the correct result, the next step is to make sure the MAF sensor has Ground, for this, go to: MAF TEST 3: Testing The 2nd Ground Circuit.

CASE 2: Your multimeter DID NOT register 12 Volts. Recheck all of your multimeter connections and retest. If you still do not see these 12 Volts, then this exonerates the MAF sensor as bad since without this Ground it's not gonna' work.

Ford Vehicles:

  • Aerostar 3.0L, 4.0L
    • 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998
  • Bronco 5.0L, 5.8L
    • 1994 1995, 1996
  • Crown Victoria 4.6L, 5.0L
    • 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002
  • Contour 2.0L, 2.5L
    • 1995 - 2000

Ford Vehicle:

  • Escape 2.0L, 3.0L
    • 2000, 2001, 2002, 2003, 2004, 2005, 2006
  • Explorer 4.0L, 5.0L
    • 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
  • E150, E250, E350 4.9L, 5.0L, 5.8L
    • 1993, 1994, 1995, 1996

Ford Vehicles:

  • Focus 2.0L
    • 2000, 2001, 2002, 2003, 2004, 2005
  • F150, F250, F350 4.9L, 5.0L, 5.8L
    • 1993, 1994, 1995, 1996
  • Mustang (GT, Cobra) 2.3L, 4.6L, 5.0L
    • 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003

Ford Vehicles:

  • Probe 2.0L
    • 1993, 1994, 1995, 1996, 1997
  • Ranger 2.3L, 2.9L, 3.0L, 4.0L
    • 1990, 1991, 1992, 1993, 1994, 1995
  • Taurus 3.0L, 3.8L
    • 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003

Ford Vehicles:

  • Tempo 2.3L, 3.0L
    • 1992, 1993, 1994
  • Thunderbird 3.8L, 4.6L, 5.0L
    • 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997

Mercury Vehicles:

  • Cougar 3.8L, 4.6L, 5.0L
    • 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997

Mercury Vehicles:

  • Grand Marquis 4.6L, 5.0L
    • 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002
  • Mountaineer 4.0L, 5.0L
    • 1997, 1998, 1999, 2000, 2001, 2002
  • Mystique 2.0L, 2.5L
    • 1995, 1996, 1997, 1998, 1999

Mercury Vehicles:

  • Sable 3.0L, 3.8L
    • 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
  • Topaz 2.3L, 3.0L
    • 1992, 1993, 1994

Lincoln Vehicles:

  • Continental 3.8L
    • 1992, 1993, 1994

Lincoln Vehicles:

  • Town Car
    • 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999

Mazda Vehicles:

  • B4000
    • 1994