Problems with your Nissan Altima Mass Air Flow (MAF) Sensor can lead to driveability problems and the OBDII DTC of P0100. This generic OBD diagnostic trouble code dictates that there’s a problem with your Altima’s MAF. The MAF is responsible for providing real time data to the ECU about the air entering the engine.
Your Nissan ECU then uses this information to operate your 2.4 liter KA24 ignition and fuel events. When your Nissan encounters issues with your mass air flow meter, or the signal being sent by this meter, your check engine light is triggered. Today I’ll be showing you how to test a Nissan Altima MAF in a 2000 Nissan Altima with the 2.4 liter engine in it.
Where is my Nissan Altima MAF Located?
The Mass Air Flow Sensor (MAF) on your 2.4 liter KA24DE equipped Nissan Altima is mounted to the air box by four 10mm bolts. These bolts screw onto the air filter housing, but you will not need to remove any of it to test your MAF.
The part number for this air flow sensor is 22680-70F00, and as expected there’s quite a few interchange part numbers. This 2.4 liter KA24 engine is found in many late model Nissan vehicles, from the Xterra, 240SX and Nissan pickup trucks. If you are having a hard time locating a MAF replacement for your KA24DE, check the following interchange part numbers :
- 22680-70F05
- 22680-9E000
- 22680-9E005
- 22680-9E000
There’s also GMC part numbers that work for your Nissan Altima, they are
- 22680-70F05
- 22680-9E000
- 226809
How To Test your Nissan Altima MAF
To begin our how to test a Nissan Altima MAF to fix the P0100 OBDII DTC trouble code, you will need to locate and disconnect your MAF. Using a multimeter, you’ll be testing the three wires at this sensor to see what is causing your P0100.
The first part of our how to test a Nissan Altima MAF test involves measuring the wiring harness for power and ground. With the MAF connector unplugged, put the black lead of your multimeter to the negative post of your battery. Now probe PIN A, which is the first pin that’s adjacent to the blank slot in your Nissan MAF.
This wire should return voltage, if not make sure you have the key inserted into the ignition and turned to the “ON” position. If you have power at this wire, move onto checking for the low reference ground signal.
Now turn the key in the ignition to the “OFF” position, and now you’ll be checking the PIN B for a low reference signal. This ground is supplied by your Nissan Altima ECU, and if you have ground here, you know that your Altima MAF is receiving power.
Measuring your Nissan Altima MAF signal
Learning how to measure your Nissan Altima’s MAF signal is very easy and simple to do. The signal wire on your Nissan Altima MAF is PIN C, and this test involves backpinning PIN C with the MAF harness connected. Take a paper clip and straighten it, insert into the BACK of your MAF connector, at the PIN C terminal.
Reconnect your MAF harness and make sure the paper clip is making contact with your signal wire terminal. This is how you will test the voltage being sent by your Nissan MAF.
- Start engine and warm up to operating temperature.
- Measure voltage at PIN C
- Measurements at idle should be around 0.45 – 0.89
- Depress throttle or manually open throttle blade to increase engine speed.
- Measure and check MAF operation
- Make sure voltage increases along with engine speed.
This test is designed to show you if your MAF is unresponsive, lazy or just plain failed. If you don’t see any voltage reading, or you see spikes or dips where there shouldn’t be, there’s one last section of our DIY guide.
Checking your Nissan Altima MAF for continuity
The signal wire for your 2.4 liter Altima MAF leads back and terminal at PIN 47 of your KA24 ECU. Check for continuity or if there are any wire breaks or shorts between your Altima MAF connector and your ECU harness.
Replace or repair the wire in question if you do find a break or short. If not, replace your Mass air flow sensor to eliminate the P0100 trouble code, and use a scan tool to clear the code.
Have any questions about our how to test a Nissan Altima MAF DIY Guide? Leave them for us below!
Followed ur guide but my code won’t go away. I got a 99 altima. Please help
Hi Mike, thanks for reading.
So you followed our guide and what value did you get at the signal wire?
I have a 97 Altima and am getting no voltage at the low reference wire is that a bad ecm
Hi James, check the wiring to make sure there’s continuity between the MAF connector and your ECM. If your Nissan Altima MAF doesn’t have voltage a the low reference, you are checking this with the MAF plugged in right?
I replaced the MAF sensor and air filter on my 2010 Altima 2.5S. Ran great for 2 days then service engine light returned along with same symptoms. What causes sensor to fail repeatedly?
Hi Bob, thanks for commenting. Have you checked the wiring to your MAF? Can you try switching back your old MAF? Is your battery voltage good? Let us know and we might be able to help!
Followed guide. Backpinned C ( red probe from multimeter with alligator clip attached to backpin). Black probe from meter to Negative battery terminal??? Was this correct??? Got a reading of 1.40. Upon accelaration rate would climb predictably. Thank you
Hi Marty, thanks for reading.
Does the MAF function properly when plugged in? Because this reading is outside the Nissan Altima specifications. If so what are the Nissan Altima problems you are having?