The DTC ODBII trouble code P0127 is an Nissan 350Z IAT Sensor fault, or IAT for short. For this particular writeup we will be addressing the replacing of said sensor in this Nissan 350Z. This sensor is nothing but a simple thermister that is sensitive to the ambient temperature of the air coming into your engine.
This temperature sensing unit changes the electrical resistance of the thermistor itself by decreasing the resistance in response to rising intake temperatures. When the P0127 trouble code is alerted, your on-board PCM or ECU has in fact determined that the intake temperature sensor has fallen out of acceptable values set by Nissan.
How your Nissan 350Z IAT Sensor works
As your 350Z is a mass airflow design, the thermistor ( or intake temperature sensor ) is located in the MAF unit itself, making the change over very easy and straightforward.
For vehicles with speed density or running manifold absolute pressure, your intake temperature sensor will be located elsewhere, most likely connected using a 2 pin weatherproof connector.
Since our VQ35 equipped vehicle has the intake temperature sensor located inside the Mass Air Flow Sensor, we will be replacing the unit as a whole, part number 22680-7S00A. This MAF is also found on the Nissan / Infiniti : Versa, Frontier, G37, G35, Sentra, Altima and much much more.
To test the Nissan 350Z IAT Sensor, you can take a look at the PCM and use terminal 34 to test for the voltage and resistance range using a ohmmeter. If you are not familiar with operating said meter, please get help before continuing onward.
**TIP When testing the terminal 34, do NOT use the ground located on the PCM as that may cause electrical issues elsewhere. Make sure to use a chassis ground!
Reference Data for Air Intake Temperature Sensor :
- Intake Air Temps : 25 deg C – Voltage 3.3 volts – resistance Ω range : 1.800-2.200
- Intake Air Temps : 80 deg C – Voltage 1.2 volts – resistance Ω range : 0.283 – 0.359
If your ohmmeter is telling you that the resistance provided or voltage is outside this range, you are in need of a replacement sensor!
Where is the Nissan 350Z IAT Sensor
The 350Z Mass Air Sensor can be removed from the body of the housing by undoing the 2 hex screws that hold the sensor in place to measure the incoming air charge. With this unit removed, you can set it to the side to see the actual filiment of the Air Intake Temperature sensor.
First disconnect your negative battery terminal to prevent any electrical issues or problems when working in your engine bay. Next undo the splash tray and intake duct that delivers fresh air to your airbox and get ready to disconnect the snorkel from the MAS and the airbox from the MAS.
Pictured is the MAS itself, you will be disconnecting this unit and taking out the sensor itself. Here’s a blown up diagram of what you are dealing with.
Once you have the unit replaced, plug in your favorite ODDII scanner and clear the code P0127 and you are ready to rock and roll!
Happy Driving!
- Pro Street Staff
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Hello! I actually have a 2013 Infinity IPL G37 Coupe 6MT. A rare car indeed. It is actually being shipped to me as we read this! My motor actually has dual intakes with dual separate air filters, etc. Since I do not physically have the car yet, I am wondering, does the motor have 2 MAF sensors with 2 IAT sensors in them; that would be one per intake tube? At the risk of being ignorant, can someone please answer my question and clarify as well? Thank you!
Rich, thanks for commenting.
Your G37 is equipped with two MAF sensors that carry a part number of 13800-66J00, 22680-7S000, and lastly part number 22680-AT300 which covers the 2003 to 2012 year range only. Please let us know if you’ve got any further questions!
Thank you so much for your reply. I thought this was the case but I needed to be sure. I still do not have the car yet altough I do own it. Am just waiting for the used car dealer from whom I bought thd car to get the right kind if title for me so I can rsgister and re-title it in FL…a very ling story. I am quite excited to get this car. Particularly because it has a real 6-speed stick. I HATE woosie-weenie matics of ANY kind including those aweful and stupid paddle shifters.
No problem at all Richard, glad we could help.
Hey, I need to find a wiring diagram for the 2 MAF sensors that include the IAT senors. I need only to get the wiring colors for both sides of the IAT’s. That is,the side that goes to the sensor as well as the side that goes to the ECU. Can anyone please help me with this request? THX! RKP
[…] DTC P0127 – How to Replace your IAT […]
Hey, I need to find a wiring diagram for the 2 MAF sensors that include the IAT senors. I need only to get the wiring colors for both sides of the IAT’s. That is,the side that goes to the sensor as well as the side that goes to the ECU. Can anyone please help me with this request? THX! RKP IM PUTING A STAG 1 CHIP IN IT JUST NEED YO KNOW WITCH WIRE TO USE
Hi Robert! You can use this guide here :
http://my.prostreetonline.com/2016/02/03/how-to-test-a-nissan-350z-maf-sensor/
This allows you to wire up anything inline to your 350Z MAF sensor! Thanks for commenting!