fuel AUDI A4 1997 B5 / 1.G APB Engine Additional Signals Checking Workshop Manual
Page 2 of 37
24-180
      
Fuel consumption signal for on-board 
computer, checking
 
     
Notes:  
     
The fuel consumption signal is calculated by the 
engine control module (on the basis of the 
injection period) and passed on to the on-board 
computer. The fuel consumption signal is taken 
from terminal 81 on the Engine Control Module 
(ECM). 
     Checking fuel consumption signal
     
       Electrical Wiring Diagrams, Troubleshooting & 
Component Locations   
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Page 7 of 37
24-184
      
Fuel tank level signal, checking
 
     
Note:  
     
The Engine Control Module (ECM) receives the 
fuel tank level signal from the instrument 
cluster. 
     The processed signal enters on terminal 30 the 
Engine Control Module (ECM) and is used to 
determine certain malfunctions (e.g.: misfire) 
     
-  Connect VAG1598/31 test box to wiring harness 
for engine control module. Do not connect to the 
engine control module itself   Page 24
-20
 . 
     
-  Check wiring from test box socket 30 to 
instrument cluster according to wiring diagram 
for an open circuit and short circuit to B+/Ground 
(GND). 
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Page 22 of 37
24-196
      
Crash signal, checking
 
      The Engine Control Module (ECM) receives the 
crash signal ("Crash shut-down activated") from 
the airbag control module.  
      If the airbag control module sends the crash 
signal to the ECM (if an accident occurred or if a 
output Diagnostic Test Mode (DTM) was carried 
out), the ECM shuts off the fuel pump, that 
means the engine stalls, however, afterwards the 
engine can be started again (e.g. when removing 
the vehicle from the accident area)  
      The ECM cannot switch off the fuel pump during 
an accident if the malfunction "Crash Signal from 
Airbag Control Unit/Range Performance" from 
the airbag control module is sent to ECM. The 
engine control module cannot recognize the 
crash signal from the airbag control module; e.g.: 
if the wiring between the ECM and the airbag 
control module is faulty.  
     
-  Connect VAG1598/31 test box to wiring harness 
for engine control module. Do not connect to the 
engine control module itself   Page 24
-20
 . 
Pa
ge 22 of 37 Additional si
gnals, checkin
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.24.6