Page 5 of 44

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Test sequence  
     
-  Connect VAS5051 tester or VAG1551 scan tool 
and select the control module for engine 
electronics using "address word" 01   Page 01
-
9 . 
     
   Engine must run at idle for this.
     
WARNING! 
     
Observe safety precautions to reduce the risk 
of accidents during road test   Page 24
-1 . 
Rapid data transfer  
HELP
Select function XX
    
When indicated on display:  
-  Press buttons -0- and -8- to select "Read Measuring Value Block" and 
press -Q- button to confirm input. 
Read Measurin
g Value Block 
Q
Input displa
y group number XXX
    
When indicated on display:  
-  Press buttons -0-, -0- and -5- to select "display group number 005" and 
press -Q- button to confirm input. 
Read Measuring Value Block 5  
1 
2 
3 
4
    
Indicated on display:  
-  Determining via road test whether vehicle speed is displayed in display 
field 3. 
-  If vehicle speed is not display, lift vehicle -if possible using a vehicle lift-
until front left wheel is free. 
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        Page 6 of 44
24-170
      
-  Connect VAG1598/31 test box at wiring harness 
to ECM, do not connect ECM   Page 24
-17
 . 
     
-  Connect VAG1527B voltage tester to sockets 3 
(B+) and 54 (VSS) of VAG1598/31 test box. 
     
-  Switch ignition on and turn front left wheel by 
hand. 
     
 
LED must blink (very brief blink signal).
      If LED does not blink:  
     
-  Check the following wire connection for open 
circuit and short circuit to Ground (GND) and B+:
     
Test box  
VAG1598/31  
Socket  
Instrument cluster  
  
Terminal  
54    Electrical Wiring Diagrams, 
Troubleshooting & Component 
Locations binder   
     
-  Repair open circuit or short circuit if 
necessary. 
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        Page 13 of 44
24-175
      
A/C system signal, checking
 
      The A/C system signal notifies the Engine 
Control Module (ECM), that the A/C system 
requires a higher idle speed to achieve the 
desired interior temperature (regardless of 
whether heating or cooling is required).  
      The increase in idle speed based on presence of 
the A/C system signal is control module 
dependent and occurs only in vehicles with All 
Wheel Drive (AWD) and manual transmission.  
     
Test sequence  
     
-  Connect VAS5051 tester or VAG1551 scan tool 
and select the control module for engine 
electronics using "address word" 01   Page 01
-
9 . 
     
   Engine must run at idle for this.Rapid data transfer  
HELP
Select function XX
    
When indicated on display:  
-  Press buttons -0- and -8- to select "Read Measuring Value Block" and 
press -Q- button to confirm input. 
Pa
ge 13 of 44 Additional si
gnals, testin
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p://127.0.0.1:8080/audi/servlet/Dis
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yp
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pair&id=AUDI.B5.FU05.24.6 
         
        
        
     
        
        Page 14 of 44

24-176
 If specified values are not obtained:  
Read Measuring Value Block 
Q
Input displa
y group number XXX
    
When indicated on display:  
-  Press buttons -0-, -5- and -6- to select "display group number 056" and press -Q-
button to confirm input. 
-  Switch on A/C system, press "Auto" button and select the lowest temperature.
-  Check indications in display field 3 and 4.
  
Display fields  
  
1   2   3   4  
Display group 056: Idle stabilization with engine at idle and operating temperature  
Display   xxx /min   xxx /min  
---  
---  
Indicated   Engine speed (actual)   Engine speed (specified)  
A/C readiness  
A/C compressor  
Functional range    
    
A/C - LOW  
A/C - HIGH  Compr. OFF  
Compr. ON  
Specified value  
720 to 820 RPM 
1)  
630 to 730 RPM 2)  760 RPM 
1)  
680 RPM 2)  A/C - HIGH  
Compr. ON  
1) Front Wheel Drive Vehicles  2) All-Wheel Drive Vehicles  
-  Connect VAG1598/31 test box at wiring harness to ECM, do not connect ECM   Page 24
-17
 .
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        Page 33 of 44
24-190
      
Rough terrain signal from ABS/EDL 
control module, checking
 
     
Notes:  
     
When the ABS/EDL control module recognizes 
that a wheel is spinning, the ABS/EDL control 
module generates the rough terrain signal. 
When the Engine Control Module (ECM) 
recognizes the rough terrain signal, combustion 
misfire recognition is switched off in the Engine 
Control Module (ECM). 
     Only check the rough terrain signal if the 
malfunction "18014 (P1606) rough terrain 
info/engine torque from ABS cont. mod. 
Electrical malfunction in circuit" is stored DTC 
memory.It is possible that the malfunction 
"Combustion misfire" is also stored in DTC 
memory as a side effect and it can be 
disregarded. 
     The wire connection and rough terrain signal 
are monitored by the Engine Control Module 
(ECM). 
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pair&id=AUDI.B5.FU05.24.6