Audi Workshop Service and Repair Manuals

Test table

Overview of test steps

Item tested	Test step
Power supply (terminal 30) for ABS hydraulic pump -V64-	–  Perform test step 1 → Anchor
Power supply (terminal 30) for ABS hydraulic unit -N55-	–  Perform test step 2 → Anchor
Power supply (terminal 75/75a) for ABS with EDL control unit -J104-	–  Perform test step 3 → Anchor
Brake light switch -F-	–  Perform test step 4 → Anchor
Resistance of speed sensor, front right -G45-	–  Perform test step 5 → Anchor
Resistance of speed sensor, front left -G47-	–  Perform test step 6 → Anchor
Resistance of speed sensor, rear right -G44-	–  Perform test step 7 → Anchor
Resistance of speed sensor, rear left -G46-	–  Perform test step 8 → Anchor
Voltage signal of speed sensor, front right -G45-	–  Perform test step 9 → Anchor
Voltage signal of speed sensor, front left -G47-	–  Perform test step 10 → Anchor
Voltage signal of speed sensor, rear right -G44-	–  Perform test step 11 → Anchor
Voltage signal of speed sensor, rear left -G46-	–  Perform test step 12 → Anchor
Coding bridge	–  Perform test step 13 → Anchor
ABS hydraulic pump -V64-	–  Perform test step 14 → Anchor
ABS warning lamp -K47-	–  Perform test step 15 → Anchor
“Brake warning” symbol in instrument cluster or display of driver information system	–  Perform test step 16 → Anchor
Traction control system warning lamp -K86-	–  Perform test step 17 → Anchor
Traction control system switch -E132-	–  Perform test step 18 → Anchor
Wiring for longitudinal acceleration sender -G251-	–  Perform test step 19 → Anchor

Test step No. 1

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
24 + 25	Power supply, terminal 30 for pump motor of hydraulic control unit	l  Ignition off
		–  Select measuring range: voltage measurement	Approx. battery voltage	–  Check wiring according to current flow diagram: t  Between contact 24 and earth t  Between contact 25 and terminal 30

Test step No. 2

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
8 + 9	Power supply, terminal 30 for hydraulic control unit	l  Ignition off
		–  Select measuring range: voltage measurement	Approx. battery voltage	–  Check wiring according to current flow diagram: t  Between contact 8 and earth t  Between contact 9 and terminal 30

Test step No. 3

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
8 + 4	Power supply (terminal 75/75a) for ABS with EDL control unit -J104-	l  Ignition on
		–  Select measuring range: voltage measurement	Approx. battery voltage	–  Check wiring according to current flow diagram: t  Between contact 8 and earth t  Between contact 4 and terminal 75/75a

Test step No. 4

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
8 + 18	Brake light switch -F-	l  Ignition off –  Select measuring range: voltage measurement
		–  Brake pedal not operated	0 V	–  Check wiring according to current flow diagram:
		–  Brake pedal operated	Approx. battery voltage	t  Between contact 8 and earth t  Between contact 18 and terminal 30

Test step No. 5

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
19 + 20	Resistance of speed sensor, front right -G45-	l  Ignition off
		–  Select measuring range: resistance measurement	1.0...1.3 kΩ	–  Check connector of speed sensor –  Move wiring to speed sensor when checking (loose contact) –  Renew speed sensor if wiring is OK.

Test step No. 6

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
1 + 2	Resistance of speed sensor, front left -G47-	l  Ignition off
		–  Select measuring range: resistance measurement	1.0...1.3 kΩ	–  Check connector of speed sensor –  Move wiring to speed sensor when checking (loose contact) –  Renew speed sensor if wiring is OK.

Test step No. 7

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
22 + 23	Resistance of speed sensor, rear right -G44-	l  Ignition off
		–  Select measuring range: resistance measurement	1.0...1.3 kΩ	–  Check connector of speed sensor –  Move wiring to speed sensor when checking (loose contact) –  Renew speed sensor if wiring is OK.

Test step No. 8

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
5 + 6	Resistance of speed sensor, rear left -G46-	l  Ignition off
		–  Select measuring range: resistance measurement	1.0...1.3 kΩ	–  Check connector of speed sensor –  Move wiring to speed sensor when checking (loose contact) –  Renew speed sensor if wiring is OK.

Test step No. 9

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
19 + 20	Voltage signal of speed sensor, front right -G45-	l  Vehicle raised l  Ignition off –  Select measuring range: voltage measurement (alternating voltage)
		–  Rotate front right wheel at approx. 1 revolution per second.	Min. 65 mV alternating voltage	–  Check speed sensor for interchanged wiring (read measured value block 001 → Anchor) –  Check installation of speed sensor and rotor → Brake system; Rep. Gr.45

Test step No. 10

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
1 + 2	Voltage signal of speed sensor, front left -G47-	l  Vehicle raised l  Ignition off –  Select measuring range: voltage measurement (alternating voltage)
		–  Rotate front left wheel at approx. 1 revolution per second	Min. 65 mV alternating voltage	–  Check speed sensor for interchanged wiring (read measured value block 001 → Anchor) –  Check installation of speed sensor and rotor → Brake system; Rep. Gr.45

Test step No. 11

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
22 + 23	Voltage signal of speed sensor, rear right -G44-	l  Vehicle raised l  Ignition off –  Select measuring range: voltage measurement (alternating voltage)
		–  Rotate rear right wheel at approx. 1 revolution per second	190... 1140 mV alternating voltage	–  Check speed sensor for interchanged wiring (read measured value block 001 → Anchor) –  Check installation of speed sensor and rotor → Brake system; Rep. Gr.45

Test step No. 12

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
5 + 6	Voltage signal of speed sensor, rear left -G46-	l  Vehicle raised l  Ignition off –  Select measuring range: voltage measurement (alternating voltage)
		–  Rotate rear left wheel at approx. 1 revolution per second	190... 1140 mV alternating voltage	–  Check speed sensor for interchanged wiring (read measured value block 001 → Anchor) –  Check installation of speed sensor and rotor → Brake system; Rep. Gr.45

Test step No. 13

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
3 + 14	Coding bridge	l  Ignition off
		–  Select measuring range: resistance measurement	0…1 Ω	–  Check wiring and contacts in plug –  Renew coding bridge if test result does not match specification

Test step No. 14

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
–	ABS hydraulic pump -V64-	l  25-pin connector connected to ABS with EDL control unit -J104- l  Ignition on l  Vehicle diagnostic, testing and information system -VAS 5051 A- connected
		–  Initiate final control diagnosis → Chapter and activate ABS hydraulic pump -V64-	Pump motor starts up	–  Switch off ignition –  Check wiring according to current flow diagram: t  Perform test step 1 t  Wiring from contact 1 of 2-pin connector at ABS hydraulic pump -V64- to control unit t  Wiring from contact 2 of 2-pin connector at ABS hydraulic pump -V64- to control unit –  If no fault is found in wiring, remove hydraulic control unit and renew hydraulic pump with valve block → Brake system; Rep. Gr.45

Test step No. 15

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
–	ABS warning lamp -K47-	l  Ignition off l  25-pin connector connected to ABS with EDL control unit -J104-
		–  Switch on ignition	ABS warning lamp -K47- should light up for 2 seconds and then go out	–  Switch off ignition –  Connect test box -V.A.G 1598/21- –  Check wiring according to current flow diagram: t  Perform test step 3 t  Check wiring between contact 16 of -V.A.G 1598/21- and instrument cluster. –  Interrogate fault memory of instrument cluster (dash panel insert) → Electrical system, self-diagnosis; Rep. Gr.01

Test step No. 16

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
–	“Brake warning” symbol in instrument cluster or display of driver information system	l  Ignition off l  25-pin connector connected to ABS with EDL control unit -J104- l  Electrical connector unplugged from one of the front speed sensors.
		–  Switch on ignition, start engine and increase engine speed to above 2000 rpm. –  Plug in electrical connector after testing is completed and interrogate and erase fault memory	“Brake warning” symbol lights up	–  Switch off ignition –  Connect test box -V.A.G 1598/21- –  Check wiring according to current flow diagram: t  Perform test step 3 t  Check wiring between contact 16 of -V.A.G 1598/21- and instrument cluster. –  Interrogate fault memory of instrument cluster (dash panel insert) → Electrical system, self-diagnosis; Rep. Gr.01

Test step No. 17

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
–	Traction control system warning lamp -K86-	l  No faults stored in fault memory l  Ignition off l  25-pin connector connected to ABS with EDL control unit -J104-
		–  Switch on ignition	Traction control system warning lamp -K86- should light up for 2 seconds and then go out	–  Switch off ignition –  Connect test box -V.A.G 1598/21- –  Check wiring according to current flow diagram: t  Perform test step 3 t  Check wiring between contact 15 of -V.A.G 1598/21- and instrument cluster. –  Interrogate fault memory of instrument cluster (dash panel insert) → Electrical system, self-diagnosis; Rep. Gr.01

Test step No. 18

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
–	Traction control system switch -E132-	l  Ignition off l  25-pin connector connected to ABS with EDL control unit -J104- l  Test step 17 performed
		–  Switch on ignition –  Operate traction control system switch -E132-	Traction control system warning lamp -K86- lights up
		–  Operate traction control system switch -E132- again	Traction control system warning lamp -K86- goes out	–  Switch off ignition –  Connect test box -V.A.G 1598/21-
8 + 15		–  Select measuring range: voltage measurement –  Switch on ignition
		–  Do not operate Traction control system switch -E132-	Approx. 0 V	–  Check fuses and wiring according to current flow diagram: t  Between contact 15 of -V.A.G 1598/21- and contact 5 of switch t  Between contact 6 of switch and terminal 15 t  Between contact 2 of switch and earth
		–  Operate traction control system switch -E132-	Approx. battery voltage	–  Renew switch if wiring is OK.

Test step No. 19

-V.A.G 1598/21- Sockets	Item tested	Test conditions and additional operations	Specification	Fault rectification if reading does not match specification
13 + 1 → Note	Wiring for longitudinal acceleration sender -G251-	l  Ignition off l  Electrical connector at longitudinal acceleration sender -G251- unplugged
		–  Select measuring range: resistance measurement	max. 1.5 Ω	–  Repair wiring according to current flow diagram
17 + 2 → Note			max. 1.5 Ω
15 + 3 → Note			max. 1.5 Ω
		–  Check wiring for short to positive or earth.	∞ Ω

1)	Contact at connector of longitudinal acceleration sender -G251-.