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Old 02-24-2011, 06:29 AM
Mike's 5040I Mike's 5040I is offline
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Location: Northern California
Join Date: Feb 2011
Posts: 20
Mein Auto: 840CI, 650I
MAF testing

Folks ,
Unfortunately, MAF's aren't simple passive resistances . They produce a voltage that is a function of the volume and density of air going by. I have attached a technical article from Bosch describing the voltage function w.r.t. air mass.
The Unit can be monitored on the engine to see if the voltage output matches the design centerline with a voltmeter . The attached description is not all - encompassing , but you should be able to access the output voltage on the sensor on you caras the other connections are ground , supply , and an air temperature voltage.
I hope this helps.
Attached Files
File Type: pdf sensors_airmass.pdf (176.0 KB, 448 views)
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