Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Mass Air Flow (MAF) & Intake Air Temperature (IAT) Sensor On-Vehicle Inspection

Mass Air Flow (MAF) & Intake Air Temperature (IAT) Sensor On-Vehicle Inspection

NOTE: Before performed this inspection, be sure to read the Precautions of ECM Circuit Inspection:N32A.

1. Turn off ignition switch and disconnect MAF & IAT sensor connector.
2. Check that voltage of MAF & IAT sensor connector (vehicle side) between terminals "1" and "2" is battery voltage when ignition switch is ON.
If faulty condition is found, check power supply circuit, ground circuit and connections.






3. Check that MAF sensor signal is outputted properly. Pinout Values and Diagnostic Parameters
If faulty condition is found, check the following.
- Wire harness and connections
- MAF sensor: Mass Air Flow (MAF) & Intake Air Temperature (IAT) Sensor Inspection