Same thing happen to me and found a bad AFM. Check my signature on AFM rebuilds. You should read approx. 1.5-4.5 volts DC while the car is running. Use the pin seconds from the left side of the connector. Must be plugged in while performing test. 1 volts DC at idle speed, 4.5 volts DC at full throttle. (air sucking in faster opens flap.)
Multimeters are very limited as tool for this test because they acquire signal relatively slowly. Ideally you want an oscilliscope. But if your AFM is really bad, you will find non linear or near zero volts even when the flap is opened.
Multimeters are very limited as tool for this test because they acquire signal relatively slowly. Ideally you want an oscilliscope. But if your AFM is really bad, you will find non linear or near zero volts even when the flap is opened.
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