PINPOINT TEST DC: Mass Air Flow (MAF) Sensor: Introduction
WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 2008 Mercury Sable, 2008 Mercury Mountaineer, 2008 Mercury Milan, 2008 Mercury Mariner, and 2008 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.
This pinpoint test is intended to diagnose the following:
- mass air flow (MAF) sensor (12B579)
- harness circuits: MAF SIG, MAF RTN, vehicle power (VPWR), power ground (PWRGND), IAT and SIGRTN
- powertrain control module (PCM) (12A650)
| 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) |
For PCM connector views or reference values, refer to the REFERENCE VALUES article.
| Vehicle | Connector | Pin | Circuit |
|---|---|---|---|
| Edge, MKX, Sable, Taurus, Taurus X |
190 Pin | B41 B42 |
MAF MAF RTN |
| Escape/Mariner | 150 (50-50-50) Pin | B32 B43 |
MAF MAF RTN |
| Expedition, Fusion, Milan, MKZ, Navigator |
140 Pin | B41 B42 |
MAF MAF RTN |
| F-150, Mark LT |
190 Pin | E25 E26 |
MAF MAF RTN |
| Focus | 190 Pin | B40 B41 |
MAF MAF RTN |
| All other vehicles | 170 Pin | E25 E26 |
MAF MAF RTN |