fuse AUDI A4 1995 B5 / 1.G AFC Engine Fuel Supply System Components Workshop Manual
Page 15 of 24
20-10
      
Fuel pump, testing
 
     
WARNING! 
     
Fire hazard! DO NOT smoke or work near 
heaters or have anything in area that can 
ignite fuel! 
     
Checking power supply  
     
Battery fully charged 
     Fuse 28 OK 
     Test voltage supply to fuse 28   Repair 
Manual, 2.8 Liter V-6 OBD II Fuel Injection 
and Ignition, Repair Group 24 
     
Fuel supply OK 
     
-  Switch ignition on.
     Fuel pump must be heard to run briefly. 
(Second person will be required for this if 
surrounding noise level is too high). 
      If fuel pump does NOT run:  
     
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Page 17 of 24
20-11
      
-  Supply voltage to fuel pump using VAG 1551 
scan tool and "Output Diagnostic Test Mode" 
function 03. 
    
-  Connect multimeter between connector terminal 1 (green wire) and 
terminal 4 (brown wire) using adapter cables from VW 1594 connector 
test kit. 
   Specified value: approx. battery positive voltage (B+)
-  If specified value is obtained, reconnect harness connector.
    
If wiring is OK:  
Checking fuel delivery   -  Using ohmmeter, check for continuity between connector (outside of 
housing), harness connector and fuel pump. 
- Replace fuel pump   page 20
-7 .
-  Install cover for fuel pump module.
Fuse 28 OK Relay in relay position 6 OK 
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Page 19 of 24
20-12
 
    
-  Disconnect fuel return line -1- at engine compartment bulkhead and 
hold in measuring container. 
-  Connect remote control VAG 1348/3A with auxiliary cable VAG 1348/2 
to fuse 28, connect positive (+) cable to battery. 
-  Operate remote control for 15 seconds (hold down button).
    
Fuel pump check valve, checking  
Testing check valve   Repair Manual, 2.8 Liter V-6 OBD II Fuel Injection 
 Ignition, Repair Group 24   -  Compare quantity of fuel delivered with specified values for minimum 
fuel delivery rate in graph, according to actual voltage at fuel pump. 
*) - Minimum fuel delivery rate-fuel volume in cm3 (ml) delivered in15 
seconds
**) - Voltage (V) at fuel pump with engine stopped, fuel pump running-
approx. 2 volts less than battery positive voltage (B+)
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11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE01.20.1