Pinpoint Test DC: Mass Air Flow (MAF) Sensor: Introduction

2007 Ford Fusion SEL, 2.3 Z, StandardSECTION Introduction
WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, 2011 Ford Fusion, 2010 Mercury Milan, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
WARNING: TO PREVENT THE RISK OF HIGH-VOLTAGE SHOCK, ALWAYS FOLLOW PRECISELY ALL WARNINGS AND SERVICE INSTRUCTIONS, INCLUDING INSTRUCTIONS TO DEPOWER THE SYSTEM. THE HIGH-VOLTAGE HYBRID SYSTEM UTILIZES APPROXIMATELY 300 VOLTS DC, PROVIDED THROUGH HIGH-VOLTAGE CABLES TO ITS COMPONENTS AND MODULES. THE HIGH-VOLTAGE CABLES AND WIRING ARE IDENTIFIED BY ORANGE HARNESS TAPE OR ORANGE WIRE COVERING. ALL HIGH-VOLTAGE COMPONENTS ARE MARKED WITH HIGH-VOLTAGE WARNING LABELS WITH A HIGH-VOLTAGE SYMBOL. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN SERIOUS PERSONAL INJURY OR DEATH.

This pinpoint test is intended to diagnose the following:

  • MAF sensor (12B579)
  • harness circuits: MAF, MAF RTN, vehicle power (VPWR), power ground (PWRGND), IAT, and SIGRTN
  • powertrain control module (PCM) (12A650)
Fig 1: Mass Air Flow/Intake Air Temperature (MAF/IAT) Sensor Connector
G07432169Courtesy of FORD MOTOR CO.
MAF/IAT SENSOR CONNECTOR PINS REFERENCE CHART

Pin Circuit
1 IAT (Intake Air Temperature)
2 SIGRTN (Signal Return)
4 MAF RTN (Mass Air Flow Return)
3 MAF (Mass Air Flow)
5 PWRGND (Power Ground)
6 VPWR (Vehicle Power)
Fig 2: Powertrain Control Module (PCM) Connector
G07432004Courtesy of FORD MOTOR CO.
PCM CONNECTOR PINS REFERENCE CHART

Pin Circuit
B40 MAF (Mass Air Flow)
B41 MAF RTN (Mass Air Flow Return)
RENDER: 1.0x

NO RELATED

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