AUDI A4 2000 B5 / 1.G Brakes Can Bus User Guide
Page 11 of 12
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Example 3: 
      Using the DTCs stored in the memories, you 
have determined that none of the control 
modules are sending or receiving signals.  
     
Control 
module  DTCs stored in DTC 
memories:  
1  
Hardware malfunctioning
2  Hardware malfunctioning
3  Hardware malfunctioning
     
-  Switch ignition off.
    
 Electrical Wiring Diagrams, Troubleshooting & Component Locations    -  Disconnect the control modules connected across the bus wires and 
check for a short circuit between the bus wires. 
    
-  Check the bus wires for short circuit to B+ or Ground (GND).
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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e=re
pair&id=AUDI.B5.SU02.01.3 
Page 12 of 12
01-34
      
- If you cannot determine a cause for the DTC 
"Hardware malfunction", check whether the DTC 
is caused by one of the control modules. 
     
   All control modules that use the CAN-bus are 
still disconnected. The ignition is switched off. 
     
  -  Connect one of the control modules.
     
  -  Connect the VAG1551 Scant Tool (ST) or the 
VAG1552 mobile scan tool. Switch ignition on, 
and erase the DTC memory of the control 
module you just connected. End scan tool 
output using the "End Output" function 06. 
     
  -  Switch ignition off and then on.
     
  -  Leave ignition on for 10 seconds. Then, read 
the DTC memory of the control module you 
just connected. 
     
  -  If the DTC "Hardware malfunction" is 
displayed, replace the control module you just 
connected. 
     
  -  If the DTC "Hardware malfunction" is not 
displayed, connect the next control module 
and repeat the procedure. 
Pa
ge 12 of 12 CAN-
bus
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.3