Air Flow Meter/Sensor: Testing and Inspection

Fig. 26 Air Flow Meter Inspection:

1. Remove air flow meterFig. 26.
2. Check air flow meter body for cracks, replacing as necessary.
3. Ensure measuring plate moves smoothly.

Fig. 28 Air flow meter connector terminal identification.:

4. Using ohmmeter, check resistance between terminals, Fig. 28, with measuring plate fully closed and fully open. There should be 20-400 ohms between terminals E2 and VS with plate fully closed and 20-1000 ohms with plate fully open, 100-400 ohms between terminals E2 and VC regardless of plate position and 200-400 ohms between terminals E2 and VB regardless of plate position. Resistance between terminals E2 and THA, regardless of plate position, should be 13.6-18.4k ohms at -4°F, 2.21-2.69k ohms at 68°F and 493-667 ohms at 140°F. Resistance between terminals E1 and FC should be infinite with plate fully closed and zero ohms with plate fully open.