24-72
      
Checking voltage supply to Mass Air Flow 
(MAF) sensor  
     
-  Disconnect harness connector from air mass 
meter. 
    
Note:  
The mass air flow sensor receives its voltage supply via the fuel pump 
relay. 
If the reading does not match the battery voltage:  
 Electrical Wiring Diagrams, Troubleshooting & Component Locations    -  Connect hand-held multimeter (voltage measurement range) between 
engine Ground (GND) and socket 2 of connector. 
-  Operate starter briefly. 
   Specification: approx. battery voltage
-  Check for open circuit or short to Ground (GND) in wiring between fuel 
pump relay and socket 2 on connector via fuse. Repair if necessary. 
Pa
ge 83 of 90 Motronic Multi
port Fuel In
jection 
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.FU04.24.1