brake AUDI A6 1996 C5 / 2.G ATW Engine Electronic Power Control Checking Workshop Manual
[x] Cancel search | Manufacturer: AUDI, Model Year: 1996, Model line: A6, Model: AUDI A6 1996 C5 / 2.GPages: 51, PDF Size: 0.3 MB
Page 38 of 51

24-143
 
  
Brake light switch and brake pedal switch, 
checking
 
Special tools and equipment  
 
VAG1526A
 VAG1527B
 VAG1594A
 VAG1598/31
 VAS5051 with VAG5051/1
- or 
 VAG1551 with VAG1551/3A
Pa
ge 38 of 51 Electronic En
gine Power Control 
(EPC
) (E-Gas
), checkin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU06.24.4 
Page 39 of 51

24-144
      
Note:  
     For safety reasons, the instruction from the 
accelerator pedal sensor (potentiometer) to the 
ECM to open the throttle valve is suppressed 
when brake is being operated. This requires the 
brake light switch signal and also the brake pedal 
switch signal in the control module. If brake pedal 
is operated with accelerator pedal constantly 
depressed, engine is immediately regulated 
down to idle speed. A faulty switch can lead to 
undesired regulation. 
     
Test sequence  
     
-  Connect VAS5051 tester or VAG1551 scan tool 
and select control module for engine electronics 
using "address word" 01   Page 01
-10
. Ignition 
must remain switched on. 
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
Enter displa
y group number XXX
    
When indicated on display  
-  Press buttons -0-, -6- and -6- to select "display group number 066" and 
press -Q- button to confirm input. 
Pa
ge 39 of 51 Electronic En
gine Power Control 
(EPC
) (E-Gas
), checkin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU06.24.4 
Page 40 of 51

24-145
 
Read Measuring Value Block 66  
1 
2 
3 
4
    
Indicated on display  
-  Check brake light/brake pedal switch in display field 2.
  
Display fields  
  
1   2   3   4  
Display group 066: Signals to Engine Control Module (ECM)  
Display  xxx km/h  
XXXX  xxx km/h  XXXX  
Indicated  ACTUAL speed  
Switch positions   SPECIFIED speed   Switch positions  
Functional range    
  XX00  
XX11       
Specified value    
XX00  
(with brake pedal not operated)       
    
XX11  
(with brake pedal operated)       
Note    
Value:X = no significance.  
Switch points slightly offset       
Pa
ge 40 of 51 Electronic En
gine Power Control 
(EPC
) (E-Gas
), checkin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU06.24.4 
Page 41 of 51

24-146
       If indications do not resemble description:  
     
Check switch  
     
-  Remove driver-side storage compartment.
     
       Repair Manual, Body Interior, Repair Group 
68; Instrument panel; Driver
-side storage 
compartment, removing
   
     
-  Disconnect harness connector at brake light 
switch and brake pedal switch. 
    
If specified values are not obtained:  -  Connect multimeter between terminal 1 and 2 for resistance 
measurement. 
 
Specification:  (no continuity)
- Depress accelerator pedal.
 
Specification: approx. 0
-  Connect multimeter between terminal 3 and 4 for resistance 
measurement. 
 
Specification: approx. 0
- Depress accelerator pedal.
 
Specification:  (no continuity)
Pa
ge 41 of 51 Electronic En
gine Power Control 
(EPC
) (E-Gas
), checkin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU06.24.4 
Page 42 of 51

-  Replace brake light switch / brake pedal switch.
Pa
ge 42 of 51 Electronic En
gine Power Control 
(EPC
) (E-Gas
), checkin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU06.24.4