AUDI A4 1998 B5 / 1.G AC System On Board Diagnostic Owner's Guide

01-24

VAG1551 scan tool
display Possible cause
Corrective action
00000
No DTC recognized If "no DTC recognized appears after performing repairs, OBD is ended.
00529 2122
Speed information
missing /SP1) - Open circuit in wiring between Engine Control Module
(ECM), instrument cluster and A/C control head -E87-
- ECM and instrument cluster supply an unusable engine
speed signal - Diagnose and repair open circuit in
wiring using wiring diagram
- Read measuring value block
page 01
-63

- Test engine speed signal
Repair Manual, Fuel Injection &
Ignition, Repair Group 24
00532 2234
Supply voltage

Signal too low /SP - Voltage drops in electrical system to levels of less than
9.5 V2)
- Contact resistance in cable connection to A/C
Refrigerant Low Pressure Switch -F73- - Test Generator (GEN) and Voltage
Regulator (VR)
Repair Manual, Engine
Mechanical, Repair Group 27
- Diagnose and repair contact
resistance using wiring diagram
1)This fault may be generated during Output Diagnostic Test Mode (DTM) (no engine speed signal recognized although A/C
compressor speed detected).
2) If voltage at -E87-connector -C3- drops below 9.5 V, compressor switches off for a minimum of 25 seconds. Compressor
switches on again when voltage exceeds 10.8 V.
Pa
ge 31 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
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11/21/2002 htt
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e=re
pair&id=AUDI.B5.HA01.01.1

01-25

VAG1551 scan tool display
Possible cause
Corrective action
00600
Temperature Regulator Flap Motor
Position Sensor -G92- for
Temperature Regulator Flap Motor
V681)
Short circuit to ground /SP

Open circuit/short circuit to
positive /SP
Adaptation limit exceeded
Mechanical malfunction. - Short circuit, open circuit in wiring or
incorrect terminal assignment (wires
interchanged) of connectors between -G92-
and -E87-
- Temperature flap not operating freely
- -G92- in -V68- inoperative- Diagnose and repair short circuit,
open circuit in wiring or confirm
terminal assignment using wiring
diagram

- Check for free operation of
temperature flap
- Replace -V68-
00601
Central Flap Motor Position Sensor
G112 in Central Air Flap Motor V70
Short circuit to ground /SP

Open circuit/short circuit to
positive /SP
Adaptation limit exceeded2)
Mechanical malfunction - Short circuit, open circuit in wiring or
incorrect terminal assignment (wires
interchanged) of connectors between -
G112- and -E87-
- Central flap not operating freely
- -G112- in V70 inoperative- Diagnose and repair short circuit,
open circuit in wiring or confirm
terminal assignment using wiring
diagram

- Check for free operation of central
flap3)
- Replace -V70-
Pa
ge 32 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
)
11/21/2002 htt
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1)If a fault exists at potentiometer -G92-, flap motor V68 can be set manually by operating "+" or "-" button for temperature
selection (display range between 0 C and 50 C). 2)This fault only recognized during the basic setting.
3)Both end stops must be reached.
Pa
ge 33 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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e=re
pair&id=AUDI.B5.HA01.01.1

01-26

VAG1551 scan tool display
Possible cause
Corrective action
00602
Footwell/Defrost Flap Motor
Position Sensor G114 in
Footwell/Defroster Flap Motor V85
Short circuit to ground /SP

Open circuit/short circuit to
positive /SP

Adaptation limit exceeded1)

Inoperative - Short circuit, open circuit in wiring or
incorrect terminal assignment (wires
interchanged) of connectors between -G114-
and -E87-
- Footwell/defroster flap not operating freely
- -G114- in -V85- inoperative- Diagnose and repair short circuit,
open circuit in wiring or confirm
terminal assignment using wiring
diagram

- Check for free operation of
footwell/defroster flap2)
- Replace -V85-
00603
Footwell/Defroster Flap Motor V85

Blocks or de-energized /SP - Short circuit, open circuit in wiring or
incorrect terminal assignment (wires
interchanged) of connectors between V85
and -E87-
- Footwell/defroster flap flap not operating
freely
- -V85- inoperative- Diagnose and repair short circuit,
open circuit in wiring or confirm
terminal assignment using wiring
diagram

- Check for free operation of
footwell/defroster flap
- Check -V85- using function 03
(Output DTM) page 01
-42

1)This fault only recognized during basic setting.
2) Both end stops must be reached.
Pa
ge 34 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
)
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.HA01.01.1

01-27

VAG1551 scan tool
display Possible cause
Corrective action
00604
Back Pressure Flap
Motor Position Sensor
G113 in Air Flow Flap
Motor V71

Short circuit to
ground /SP

Open circuit/short
circuit to positive /SP

Adaptation limit
exceeded1)

Inoperative - Short circuit, open circuit in wiring or incorrect terminal
assignment (wires interchanged) of connectors between -
G113- and -E87-
- Air flow flap not operating freely
- -G113- in -V71- inoperative- Diagnose and repair short circuit,
open circuit in wiring or confirm
terminal assignment using wiring
diagram

- Check for free operation of air flow
flap2)
- Replace -V71-
00625
Road speed signal

Implausible signal /SP - Loose terminal in wiring/connections between
Speedometer Vehicle Speed Sensor (VSS) G22, the
instrument cluster or in another component also
connected to this signal (e.g. radio or control module for
cruise control) and -E87-
- Speedometer -G21- or instrument cluster supplying
unusable signal or a component disrupts signal - Diagnose and repair loose terminal
using wiring diagram.





Pa
ge 35 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
)
11/21/2002 htt
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play?action=Goto&t
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e=re
pair&id=AUDI.B5.HA01.01.1

- Test road speed signal from
Speedometer G21 or from instrument
cluster (check all components
connected to this circuit using wiring
diagram)
1)This DTC only recognized during basic setting.
2)Both end stops must be reached.
Pa
ge 36 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
)
11/21/2002 htt
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.HA01.01.1

01-28

VAG1551 scan tool display
Possible cause
Corrective action
00779 3133
Outside Air Temperature Sensor G17

Short circuit to ground /SP

Open circuit/short circuit
to positive /SP - Short circuit or open
circuit
between -G17- and -
E87-
- -G17- malfunction- Diagnose and repair short circuit or open circuit in
wiring using wiring diagram
- -G17- electrical test page 01
-115
00785 3211
Instrument Panel Interior Temperature
Sensor G56

Short circuit to ground /SP

Open circuit/short circuit to
positive /SP - Short circuit or open
circuit
between -G56- and -
E87-
- -G56- malfunction- Diagnose and repair short circuit or open circuit using
wiring diagram
- -G56- electrical test page 01
-115
00787 3213
Fresh Air Intake Duct Temperature
Sensor G89

Short circuit to ground /SP
- Short circuit or open
circuit
between -G89- and -
E87-
- -G89- malfunction- Diagnose and repair short circuit or open circuit in
wiring using wiring diagram
- -G89- electrical test page 01
-115
Pa
ge 37 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
)
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.HA01.01.1

Open circuit/short circuit to
positive /SP
Pa
ge 38 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
)
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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e=re
pair&id=AUDI.B5.HA01.01.1

01-29

VAG1551 scan tool display
Possible cause
Corrective action
00797 3241
Sunlight Photo Sensor G107

Open circuit/short circuit to positive /SP

Short circuit to ground /SP - Short circuit or open
circuit
between -G107- and -
E87-
- Connections to -
G107-
interchanged
- -G107- malfunction- Diagnose and repair short circuit or open circuit in
wiring using wiring diagram
- Confirm connection using wiring diagram

- Test G107 using function 08
(Read measuring value block) page 01
-63
- Replace -G107-
00799 3243
A/C Engine Coolant Temperature (ECT)
Sensor G1101)

Open circuit/short circuit to positive /SP

Short circuit to ground /SP - Short circuit or open
circuit
between -G110-1) and
-E87-
- -G110-1) malfunction- Diagnose and repair short circuit or open circuit in
wiring using wiring diagram
- Test -G110-1) using function 08
(Read measuring value block)
page 01
-63

1) Not on USA/CDN models.
Pa
ge 39 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
)
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pair&id=AUDI.B5.HA01.01.1

01-30

VAG1551 Scan Tool display
Possible cause
Corrective action
00785 3211
Instrument panel
interior temperature
sensor
-G56
Short circuit or open circuit between
instrument panel interior temperature
sensor -G56- and A/C control head -E87- - Locate short circuit or open
circuit using wiring diagram and
repair
Short circuit to
Ground /SP
Open/Short
circuit to B+ /SP Instrument panel interior temperature
sensor -G56- malfunctioning - Check instrument panel interior
temperature sensor -G56-
electrical testing, page 01
-115

Note for DTC 00785:
For the A/C control head -E87-, the instrument panel interior temperature sensor -G56- is installed with only one display in the
A/C control head -E87-. instrument panel interior temperature sensor-G56- cannot be checked or replaced individually, if
malfunctioning replace A/C control head -E87- completely. VAG1551 Scan Tool display
Possible cause
Corrective action
00796 6) 3234
Interior temperature
sensor fan-V42
Open circuit in power supply to -V42- or in
wiring connection between -V42- and -E87- - Locate and repair open
circuit using wiring diagram
Blocked or no
voltage /SP Interior temperature sensor fan -V42-
malfunctioning - Replace A/C control head -
E87-
6) For an A/C control head -E87- with only one display, the interior temperature sensor fan -V42- is installed in the A/C control
head -E87-; if malfunctioning replace complete unit.
Pa
ge 40 of 91 A/C s
ystem, On Board Dia
gnostic
(OBD
)
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.HA01.01.1