ignition AUDI A4 1996 B5 / 1.G AEB ATW Engines Charge Air System With Turbocharger Workshop Manual
[x] Cancel search | Manufacturer: AUDI, Model Year: 1996, Model line: A4, Model: AUDI A4 1996 B5 / 1.GPages: 42, PDF Size: 0.54 MB
Page 4 of 42

21-49
      
Note:  
     The recirculating valve for turbocharger -N249- 
and wire connections are monitored by the 
Engine Control Module (ECM). 
     
-  Connect VAS5051 tester or VAG1551 scan tool 
and select control module for engine electronics 
using "address word 01". Engine must run at idle 
for this: 
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 01         If a malfunction relating to the recirculating valve 
for turbocharger -N249- is displayed:  
     
-  Disconnect hoses from valve; harness connector 
remains connected. 
     
-  Attach assisting hose to one connection of 
valve. 
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Page 5 of 42

21-50
      
-  Initiate output Diagnostic Test Mode (DTM) and 
activate the recirculating valve for turbocharger -
N249-: 
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 01   Output Diagnostic Test Mode Recirc. valve for turbochar
ger -N249
    
Indicated on display  
If valve does not click:  
If valve does not open and close properly:  
Checking internal resistance      Valve must click...
   ...and must open and close (can be tested by blowing into assisting 
hose). 
-  Check internal resistance of valve.
-  Replace recirculating valve for turbocharger -N249-.
-  Disconnect harness connector at valve.
    
-  Connect multimeter at valve for resistance measurement.
 
Specified value: 27-30 
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Page 8 of 42

21-52
       If LED does not light:  
     
-  Check wire connection from terminal 1 to Fuel 
Pump (FP) relay via fuse for an open circuit": 
     
       Electrical Wiring Diagrams, Troubleshooting & 
Component Locations        
-  Repair open circuit if necessary.
      If wire connection is OK:  
     
-  Check Fuel Pump (FP) relay:
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 24         If LED lights:  
     
- Check activation:
     
Checking activation  
    
-  Connect VAG1527B voltage tester to connector terminals 1 (B+) and 2.
- 
Initiate output Diagnostic Test Mode (DTM) and activate the 
Pa
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play?action=Goto&t
yp
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pair&id=AUDI.B5.GE02.21.3 
Page 9 of 42

 Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel Injection & Ignition, 
Repair Group 01    recirculating valve for turbocharger -N249-:  
LED must blink.
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Page 10 of 42

21-53
       If LED does not blink or if it remains constantly 
lit:  
     
-  Connect VAG1598/31 test box at wiring harness 
to ECM, do not connect ECM: 
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 24   
    
If wire connection is OK:  
 Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel Injection & Ignition, 
Repair Group 24    -  Check the following wire connection for open circuit and short circuit to 
Ground (GND) and B+: Harness connector  
terminal  
VAG1598/31 test box  
socket  
2   105  
-  Repair open circuit or short circuit if necessary.
-  Replace Engine Control Module (ECM):
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Page 12 of 42

21-55
      
Test requirements  
     
All hoses and wires have been checked for 
proper seating and seal. 
     DTC memory checked 
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 01   
     
Output Diagnostic Test Mode (DTM) 
performed 
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 01   
     
Vehicle tester VAS 5051 or VAG 1551 
connected. 
     
Test sequence  
     
WARNING! 
     
To reduce the risk of accident or injury while 
carrying out tests and measurements during 
a road test, observe safety precautions   
Page 21
-40
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Page 16 of 42

21-58
      
Note:  
     The height of the charge air pressure should be 
determined using the VAG1397/A turbocharger 
test tool, the VAS5051 tester or the VAG1551 
Scan Tool is used to determine whether the 
charge air pressure is also being recognized in 
the control module. 
    
Specification on VAG1397A: 1.450-1.700 bar
Read Measuring Value Block 115 3000 RPM 
42% 
1770 mbar 
1770 mbar
    
If the specification is exceeded or not met:  
 Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel Injection & Ignition, 
Repair Group 01   
Specified value on VAS 5051 or VAG 1551 Display field 4: 1450-1700 
mbar 
-  Check DTC memory of Engine Control Module (ECM):
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Page 19 of 42

21-61
      
Note:  
     The wastegate bypass regulator valve -N75- and 
wire connections are monitored by the Engine 
Control Module (ECM). 
     
-  Connect VAS5051 tester or VAG1551 scan tool 
and select control module for engine electronics 
using "address word 01". Engine must run at idle 
for this: 
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 01        
-  Check DTC memory of Engine Control Module 
(ECM): 
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 01         If a malfunction relating to the wastegate bypass 
regulator valve -N75- is indicated:  
     
-  Disconnect hoses from valve; harness connector 
remains connected. 
     
- 
Attach assisting hose to one connection of 
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pair&id=AUDI.B5.GE02.21.3 
Page 21 of 42

21-62
      
-  Initiate output Diagnostic Test Mode (DTM) and 
activate the wastegate bypass regulator valve -
N75-. 
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 01   Output Diagnostic Test Mode Waste
gate B
ypass Re
gulator Valve -N75
    
Indicated on display  
If valve does not click:  
If valve does not open and close properly:  
Checking internal resistance      Valve must click...
   ...and must open and close (can be tested by blowing into assisting 
hose). 
-  Check internal resistance of valve.
-  Replace wastegate bypass regulator valve -N75-.
-  Disconnect harness connector at valve.
    
-  Connect multimeter at valve for resistance measurement.
 
Specified value: 25-35 
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ge air s
ystem with turbochar
ger 
(en
gine code ATW
)
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yp
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Page 23 of 42

21-64
       If wire connection is OK:  
     
-  Check Fuel Pump (FP) relay:
     
       Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel 
Injection & Ignition, Repair Group 24         If LED lights:  
     
Checking activation  
    
 Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel Injection & Ignition, 
Repair Group 01   
If LED does not blink or if it remains constantly lit:  
 Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel Injection & Ignition, 
Repair Group 24    -  Connect VAG1527B voltage tester to harness connector terminals 1 
(B+) and 2. 
-  Initiate output Diagnostic Test Mode (DTM) and activate the wastegate 
bypass regulator valve -N75-.  
LED must blink.
-  Connect VAG1598/31 test box at wiring harness to ECM, do not 
connect ECM: 
Pa
ge 23 of 42 Char
ge air s
ystem with turbochar
ger 
(en
gine code ATW
)
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE02.21.3