warning AUDI A4 1999 B5 / 1.G Brakes ESP Bosch 5.3 Workshop Manual

01-222

Warning light functions, overview


If On Board Diagnostic (OBD) has detected a
malfunction in the system, it indicates the
malfunction by lighting up warning lamps when
ignition is switched on. The warning lamps are
located in the instrument cluster.

Instrument cluster without DIS
The illustration shows the ABS/EDL warning light -K47- (right arrow),
the warning light for brake system -K118- (center arrow, red symbol
for "brake system malfunction") and the traction control indicator light -
K86- (left arrow).

Instrument cluster with DIS
Repair manual, Brake System, Repair Group 46

For DIS, there is no warning light for brake system -K118-. The red
"brake system malfunction" symbol appears in the display. If the ABS/EDL warning light -K47 and the red symbol for "Brake
system malfunction" are not lit, but the brake system is not functioning
properly, check for malfunctions in the mechanical/hydraulic brake
system components.
Pa
ge 6 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

01-223

"Brake
malfunction"
symbol ABS/EDL
warning light
-K47- Traction control
indicator light
-K86- Possible reasons why the indicator lamps light up
off off off
All indicator lights go out after the self-test (approximately three
seconds after the ignition is switched on). All systems are OK.
Pay attention to the notes on the next page
off off blinking ASR/ESP is in adjustment mode. The ASR/ESP indicator light
blinks approximately 3 times per second.
Pa
ge 8 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

01-224

"Brake
malfunction"
symbol ABS/EDL
warning
light
-K47- Traction
control
indicator
light
-K86- Possible reasons why the indicator lamps light up
off on on
A self-test is performed after the ignition is switched on. If all systems
are OK, warning lights, the ABS warning light -K47- and traction
control indicator light -K86- go out after approximately three seconds.
If the indicator lamps do not light up, check the relevant lamps carry
out "Electrical Test", steps 17 and 19. The possible causes are as
follows:

Electrical Wiring Diagrams, Troubleshooting & Component Locations
Repair Manual, Electrical Equipment, Repair Group 90.



The battery voltage is insufficient. None of the lamps in the instrument
cluster light up. Check the battery. The ABS warning light -K47- does not light up during the self-test. There
is a short to Ground (GND) in the wiring that controls the ABS/EDL
warning light between terminal 32 of the ABS control module -J104- and
the instrument cluster. This malfunction does NOT influence the control
of the traction control indicator light.
Pa
ge 9 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

The traction control indicator light -K86- does not light up during the self-
test; carry out "Electrical test", step 19.This malfunction does NOT
influence the control of the ABS warning light.
Pa
ge 10 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

01-225

"Brake
malfunction"
symbol ABS/EDL
warning
light
-K47- Traction
control
indicator light
-K86- Possible reasons why the indicator lamps light up
off off off

There is an irregularity. The indicator lamps go on during the self-
test and then go out. The possible causes are as follows: The voltage supply for the ABS control module -J104- is between
7 and 10 volts and the vehicle speed is < 6 km/h. Carry out
"Electrical test", step 21. The DTC "01119 gear recognition signal" is stored in the DTC
memory. Check DTC memory page 01
-356
.
The signal indicating whether the parking brake is set or released
is not being sent to the ABS control module -J104-. "Read
measuring value block" function 08 page 01
-256
, display group
2 page 01
-261
.
Check the brake light switch -F-. "Read measuring value block"
function 08 page 01
-256
, display group 2 page 01
-261
.
Check the zero position of the steering angle sensor -G85-. "Read
measuring value block" function 08 page 01
-256
, display group
5 page 01
-270
.
Pa
ge 11 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

01-226

"Brake
malfunction"
symbol ABS/EDL
warning
light
-K47- Traction
control
indicator
light
-K86- Possible reasons why the indicator lamps light up
off on on
Also observe notes on the next page.
The indicator lights did not go out after the self-test. However, the red
"brake system malfunction" symbol did not go on. The On Board
Diagnostic recognized a malfunction, which deactivated the
ABS/EDL/ASR/ESP. However, the "Electronic Brake Distribution" (EBD)
remained activated. Check DTC memory page 01
-356
.
The ESP driving test may have been activated page 01
-250
Check the voltage supply for the red "brake system malfunction" symbol.
Carry out "Electrical test", step 18. If the control is malfunctioning, see
the next example for lighted indicator lights. During the last drive, a dynamic malfunction of the wheel speed sensor
occurred or a malfunction in the ABS return flow pump -V39- occurred.
In this case, the indicator lights automatically go off after the vehicle is
started, and has exceeded a speed of 2.75 km/h or a check of the return
flow pump indicated it is OK.
Pa
ge 12 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

01-227

"Brake
malfunction"
symbol ABS/EDL
warning
light
-K47- Traction
control
indicator
light
-K86- Possible reasons why the indicator lamps light up
off on on
Continuation from preceding page.
A DTC is stored in the DTC memory the first time the vehicle exceeds 6
km/h, if the voltage supply to the ABS control module -J104- is between
7 and 10 volts and the indicator lights go on. If during the drive, the
voltage supply to the ABS control module -J104- exceeds 10 volts, the
indicator light go out. The DTC remains in the memory. "Check DTC
memory" page 01
-356
.
off on off
The ESP driving test was not completed; page 01
-250
Pa
ge 13 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

01-228

"Brake
malfunction"
symbol ABS/EDL
warning
light
-K47- Traction
control
indicator
light
-K86- Possible reasons why the indicator lamps light up
on on on The ABS and traction control indicator lights go on, and three seconds after
the ignition is switched on the red "brake system malfunction" symbol goes
on.
WARNING!
The brake system is only partially functional. Because brake pressure at
the rear wheels is no longer regulated vie Electronic Brake Distribution
(EBD), the rear wheels can lock even during light braking (excessive
braking at rear axle). This can cause the rear of the vehicle to break
loose and thereby cause and accident.
Note: For vehicles with automatic transmission, the red "brake system
malfunction" symbol does not appear immediately after the ignition is
switched on. Instead, the note "Depress brake pedal before engaging gear"
appears in the display. Press the brake pedal and select a gear. The red
brake warning light appears, if the light control is working properly.
A malfunction deactivated the ABS/EDL, ASR/ESP and the "Electronic
Brake Distribution" (EBD).Check DTC memory page 01
-356
. Pa
ge 14 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

01-229

"Brake
malfunction"
symbol ABS/EDL
warning
light
-K47- Traction
control
indicator light
-K86- Possible reasons why the indicator lamps light up
off off on
The traction control indicator light does not turn off after the self-
test.


There is a malfunction that only affects the traction control. The
ABS/EDL and EBD systems are not deactivated. Check DTC
memory page 01
-356
.
Traction control has been switched off using the traction control
button. If the traction control indicator light does not light up in this
case, check the switch and the indicator light, carry out the
"Electrical test", steps 19 and 20. Short circuit to B+ in the ASR/ESP button: The traction control
indicator light goes out five minutes after the ignition is switched on.
Carry out "electrical test", step 20. There is a short to Ground (GND) in the wiring that controls the
traction control indicator light between terminal 31 of the ABS
control module -J104- and the instrument cluster. Carry out
"electrical test", step 19.
Pa
ge 15 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14

01-230

"Brake
malfunction"
symbol ABS/EDL
warning
light
-K47- Traction
control
indicator light
-K86- Possible reasons why the indicator lamps light up
on on off
No DTCs are stored in DTC memory. The ABS and traction control
warning lights do not go out after the self-test, and three seconds
after the ignition is switched on the red "brake system malfunction"
symbol goes on. There is an open circuit or short circuit to B+ in the wiring that
controls the traction control indicator light between terminal 32 of
the ABS control module -J104- and the instrument cluster; carry
out "Electrical test" step 17. Voltage supply for control module less than 7 volts; carry out
"Electrical test" step 21.
on off off
No DTCs are stored in DTC memory. The red "brake system
malfunction" symbol remains lit after the ignition is switched on.
The brake fluid level is too lowMalfunction in instrument cluster: Carry out "Electrical test", step
18.
Pa
ge 16 of 27 Electronic Stabilization Pro
gram
(ESP
) Bosch 5.3
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.SU02.01.14