seat Workshop Repair Guides

SEAT Workshop Service and Repair Manuals

ABOUT US
Clutch pedal switch: check > < Coolant temperature transmitter: check

Leon Mk2

Brake light and brake pedal switches: check
Brake light and brake pedal switches: check
As the injection system works with a transmitter on the accelerator pedal (potentiometer), which may fail, for safety purposes the engine speed is cut when the brake is activated. To these effects, the control unit requires the signal from the brake light switch and also the signal of the brake pedal. This means, therefore, that if the brake is pressed with the acclerator constantly pressed, the engine speed is cut immediately and falls to idle. If the switches are misadjusted, the speed may accidently be cut.
Special tools and workshop equipment required
t  Fault reader -V.A.G 1551- or vehicle system checker -V.A.G 1552- with cable -V.A.G 1551/3B-
t  Checking box -V.A.G 1598/22-
t  Manual multimeter -V.A.G 1526 A- or multimeter -V.A.G 1715-
t  Auxiliary measuring set -V.A.G 1594 C-
t  Current circuit diagrams
Checking conditions
l  Fuse number 20, correct.
l  Battery voltage, 11.5 V minimum.
l  All electrical consumers, for example: the lights and heated windscreen, must be turned off.
Checking process
–  Connect the -V.A.G 1551- (-V.A.G 1552-), and using the corresponding “direction code” 01, select the control unit for engine electronics. When doing this, the ignition must be on. (Fault reader: Turn on and select the control unit for engine electronics → Chapter).
   
Indication on the display:
–  Press the keys 0 and 8 for the function “Read measurement value block” and confirm with Q.
  
Fast data transmission              HELP
Select function XX
Indication on the display:
–  Press the keys 0, 0 and 6 for “Indication group number 6” and confirm with Q.
  
Read measurement value block            
Enter value group number XXX
–  Observe the indication in field 2. Theoretical value: 0 0 0
  
Read measurement value block 6        ->
0 Kph           0 0 0             000000
–  Press the brake slowly. Theoretical value: 0 1 1
The digits must change at the same time from 0 to 1.
t  central value = brake pedal switch
t  right value = brake light switch
  
Read measurement value block 6        ->
0 Kph           0 1 1             000000
–  Allow the brake pedal to slowly return to its rest position.
The two figures must slowly change from 1 to 0.
If one or both the figures fail to change:
–  Check the switches or the cabling to the switches → Current flow diagrams, Electrical fault finding and Fitting locations.
  
Read measurement value block 6        ->
0 Kph      0 0 0         000000      255

Clutch pedal switch: check > < Coolant temperature transmitter: check