Air Flow Meter/Sensor: Testing and Inspection
MASS AIR FLOW (MAP) SENSOR INSPECTIONVisual Inspection
NOTE: Perform the following inspection only when directed.
1. Visually inspect for the following on the MAF sensor.
- Damage
- Cracks
- Terminal bends
- Terminal rust
- If any of the above are found, replace the MAF sensor.
- If the MAF PID value is out of specification, carry out the "Circuit Open/Short Inspection".
Circuit Open/Short Inspection
1. Disconnect the PCM connector.
2. Disconnect the MAF sensor connector.
3. Inspect the following wiring harnesses for open or short. (Continuity check)
Open circuit
- If there is no continuity, the circuit is open. Repair or replace the harness.
- MAF sensor terminal A (harness-side) and main relay terminal C (harness-side)
- MAF sensor terminal B (harness-side) and PCM terminal 2AC (harness-side)
- MAF sensor terminal C (harness-side) and PCM terminal 1P (harness-side)
Short circuit
- If there is continuity, the circuit is shorted. Repair or replace the harness.
- MAF sensor terminal A (harness-side) and body GND
- MAF sensor terminal C (harness-side) and power supply
- MAF sensor terminal C (harness-side) and body GND
- MAF sensor terminal B (harness-side) and power supply