Page 6 of 79

01-65
 Test table: display group 2  Read measuring value block  
2   
 Indicated on display  
0 or 1  
  0 or 1  
  
0 or 1  
  0 or 1  
    
     
  
ABS solenoid valve relay:  
For vehicles with Front Wheel Drive (FWD), the display shifts one field toward 
left.  
0   not permitted during "Read measuring value block", the relay was not 
activated during "ignition on". 
- Carry out "Electrical test", step 11   page 01
-68
 .
1   specified value, relay was activated by ABS control module -J104- during 
ignition on. 
     
Voltage at motor for ABS return flow pump:  
For vehicles with Front Wheel Drive (FWD), the display shifts one field toward left.  
 
0   specified value, there is no voltage at the motor for the ABS return flow pump. 1   not permitted during "Read measuring value block", there is voltage at the motor for the 
ABS return flow pump. 
- Carry out "Electrical test", step 12   page 01
-68
 . 
  
Brake light switch: Additional signal only for 
All Wheel Drive (AWD):    
Pa
ge 6 of 79 Read Measurin
g Value Block 
(function 08
)
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        Page 7 of 79
0   Brake pedal not operated1   Brake pedal operated
  
 Electrical Wiring Diagrams, Troubleshooting & Component 
Locations    - Check brake light switch if there are deviations.
Brake light switch: Signal for Front 
and All Wheel Drive:  
 
0   Brake pedal not operated  1   Brake pedal operated 
  
  
 Electrical Wiring Diagrams, Troubleshooting & Component Locations    - Check brake light switch if there are deviations.
Pa
ge 7 of 79 Read Measurin
g Value Block 
(function 08
)
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8 
         
        
        
     
        
        Page 19 of 79

01-74
 
Terminal  
Wire connection to component ...  
37  
Hydraulic unit; activation of ABS solenoid valve relay -J106-  38  
Right rear ABS wheel speed sensor -G44-  42  
Right front ABS wheel speed sensor -G45-  
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR for vehicles with All Wheel Drive (AWD) and ABS/EDL (throttle valve regulation)
44  
Traction control (ASR) button  
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR 
45  
TI (Transmission Influence)  
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR 
46  
K-wire  47  
Engine Control Module (ECM); AET (Actual Engine Torque)  
for vehicles with Front Wheel Drive (FWD) and ABS/EDL/ASR 
47  
Brake light switch -F-  
for vehicles with All Wheel Drive (AWD) and ABS/EDL
48  
Brake light switch -F-  50  
Battery + (terminal 30)  53  
Hydraulic unit; left rear ABS inlet valve -N134-  
Pa
ge 19 of 79 Read Measurin
g Value Block 
(function 08
)
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yp
e=re
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        Page 44 of 79

01-89
 
Function test: ABS warning light -K47-  
Test step  
VAG  
1598/20 
sockets  Test of  
Test 
requirements 
- Additional work 
steps Specified value  
Corrective action  
19  
  
Continuation:  -   Function of 
ABS 
warning 
light -K47-  - Switch on 
ignition ABS warning 
light -K47- lights 
up for two (2) 
seconds and 
then goes out.  
 Electrical Wiring Diagrams, 
Troubleshooting & Component Locations    - If ABS warning light does not come on, 
check voltage of electrical system and test 
wiring from terminal 32 of ABS control 
module -J104- to instrument cluster for 
short circuit to Ground (GND). 
- The ABS warning lamp does not switch 
off after 2 seconds. The red "brake system 
malfunction" symbol lights up after 2 
seconds. Check wire from terminal 32 of 
ABS control module -J104- to instrument 
cluster for short circuit to B+ and open 
circuit. 
              
 Repair Manual, Electrical Equipment, 
Repair Group 90; Instrument cluster
    - Are both the vehicle voltage and the 
wiring from terminal 32 of ABS control 
module -J104- to the instrument cluster 
OK?   Malfunction in instrument cluster. Pa
ge 44 of 79 Read Measurin
g Value Block 
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8 
         
        
        
     
        
        Page 45 of 79
01-90
 
Function test: Red brake warning symbol  
Test 
step  VAG  
1598/20 
sockets  Test of  
Test requirements 
- Additional work stepsSpecified 
value  Corrective 
action  
20   -   Function of red "brake 
system malfunction" 
symbol  
 Repair Manual, Brake System, Repair 
Group 47
   
Brake fluid level is OK Function of ABS warning light -K47- 
already checked in step 19. Multi-pin connector connected to ABS 
control module -J104- and retainer 
catch engaged. Switch on ignition      
            Test step 20: Continued on 
next page.  
Pa
ge 45 of 79 Read Measurin
g Value Block 
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8 
         
        
        
     
        
        Page 46 of 79
01-91
 
Function test: Red brake warning symbol  
Test step  
VAG  
1598/20 
sockets  Test of  
Test requirements 
- Additional work stepsSpecified value  
Corrective action  
20  
  
Continuation:     Function of red 
"brake system 
malfunction" 
symbol  - For vehicles with 
automatic transmission and 
high-line instrument cluster, 
depress the brake pedal 
and select a driving gear. The ABS/EDL indicator 
lamp and the red "brake 
system malfunction" 
symbol light up. If the 
traction control indicator 
light is installed and OK, it 
also lights up.   Repair Manual, 
Electrical Equipment, Repair Group 90; Instrument cluster
    - Malfunction in 
instrument cluster 
Pa
ge 46 of 79 Read Measurin
g Value Block 
(function 08
)
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8 
         
        
        
     
        
        Page 68 of 79
01-109
 
Output on printer of 
VAG1551 Scan Tool 
(ST)  Possible cause  
Corrective action  
DTC       
00526        
Brake light switch -F-        
FWD:  
Open circuit   
Both brake lights -M9- (left) and -M10- (right) 
malfunctioning or ABS control module -J104- 
malfunctioning. 
 Wire from brake lights to control module faulty. Electrical Wiring Diagrams, 
Troubleshooting & Component 
Locations    - Locate and repair open circuit or 
short circuit. 
- Replace bulbs.
- Check brake light switch, "Read 
measuring value block", display 
group 2   page 01
-65
 . 
AWD:  
Implausible signal   
Open circuit or short circuit to B+ or Ground (GND) in 
wiring between brake light switch and the bulbs for brake 
lights -M9- (left), -M10- (right) or ABS control module -
J104-. 
 Bulb for left brake light -M9- or right brake light -M10- 
malfunctioning. 
 Brake light switch malfunctioning.  
Pa
ge 68 of 79 Read Measurin
g Value Block 
(function 08
)
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.8