Operation CHARM: Car repair manuals for everyone.

Air Flow Meter/Sensor: Testing and Inspection

MASS AIR FLOW (MAP) SENSOR INSPECTION

NOTE: Perform the following inspection only when directed.

Visual Inspection

1. Visually inspect for the following on the MAF/IAT sensor.
- Damage
- Cracks
- Bent terminals
- Terminal rust
- If any of the above are found, replace the MAF/IAT sensor.

MAP Rate and Load Value






NOTE: The scan tool shows the MAF rate and load value.

Circuit Open/Short Inspection




1. Disconnect the PCM connector.
2. Inspect the following harnesses for open or short circuit. (Continuity check)

Open circuit
- MAF/IAT sensor terminal A and main relay terminal C
- MAF/IAT sensor terminal B and PCM terminal 10
- MAF/IAT sensor terminal C and PCM terminal 11

Short circuit
- MAF/IAT sensor terminal A and body GND
- MAF/IAT sensor terminal B and power supply
- MAF/IAT sensor terminal C and power supply
- MAF/IAT sensor terminal C and body GND