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Audi Workshop Service and Repair Manuals

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Checking F36 clutch pedal switch F36 > < Checking fuel level signal wiring

A4 Mk1

Motronic injection and ignition system (6 cyl. turbo)
Checking auxiliary signals
Checking brake light switch and brake pedal switch

Test sequence

  • ‒ Connect up vehicle diagnostic, testing and information system VAS 5051 or fault reader V.A.G 1551 and select engine electronics control unit with "Address word" 01 .
    For this purpose, the ignition must be switched on.
 
→ When adjacent display appears:
Rapid data transfer    HELP
Select function XX
  • ‒ Enter "08" to select the function "Reading measured value block" and confirm entry with Q key.
 
→ When adjacent display appears:
Reading measured value block    Q
Enter display group number XXX
  • ‒ Enter "066" for "display group number 066" and confirm entry with Q key.
 
→ Display:
Read measured value block 66    ⇒
    1    2    3    4
  • ‒ Check brake light/brake pedal switch in display zone 2.

Display zones

1

2

3

4

Display group 066: Signals to engine control unit

Display

xxx km/h

XXXX

xxx km/h

XXXX

Display

ACTUAL speed

Switch settings

SPECIFIED speed

Switch settings

Range


XX00
XX11

Specified value

XX00
(with brake pedal
not pressed)

XX11
(with brake pedal
pressed)

Note:

Value:
X = no meaning.
Switching points are slightly offset

If the display is not as described:

Checking switch

  • ‒ Remove driver's storage compartment.

=> General Body Assembly - Interior; Repair Group 68; Dash panel; Removing driver's shelf

  • ‒ Unplug connector from brake light/brake pedal switch.
  • ‒ Connect multimeter between contacts 1 and 2 to measure resistance.

Note:

Receptacles are marked on back of plug.

    • ‒ Specified value: ∞ω (no continuity)
  • Press brake pedal.
    • ‒ Specified value: approx. 0 ω
  • Connect multimeter between contacts 3 and 4 to measure resistance.
    • ‒ Specified value: approx. 0 ω
  • Press brake pedal.
    • ‒ Specified value: ∞ω (no continuity)

If specified values are not attained:

  • ‒ Check adjustment or replace brake light/brake pedal switch.

If specified values are attained:

Checking power supply

  • ‒ Connect voltage tester V.A.G 1527 B as follows:

Connector
contact

Measure to

1

Car body earth point
    • ‒ The LED should light up.

Connector
contact

Measure to

3

Car body earth point
  • ‒ Switch the ignition on.
    • ‒ The LED should light up.

If the LED does not light up:

  • ‒ Check the wiring between contact 1 and 3 of connector for open circuit (fuse) or short to earth:

=> "Current Flow Diagrams, Electrical Fault-finding and Fitting Locations" binder

  • ‒ Rectify any open/short circuit as necessary.

If the LED lights up:

Checking actuation

  • ‒ Connect the V.A.G 1598/31 test box to wiring harness leading to engine control unit; the engine control unit should not be connected => Page 24-22.
  • ‒ Check for open circuit and short to earth/positive or earth in the following wiring connections:

Connector
contact

Test box V.A.G 1598/31
socket

2

56

4

55
  • ‒ Rectify any open/short circuit as necessary.

Checking F36 clutch pedal switch F36 > < Checking fuel level signal wiring