light AUDI A4 1998 B5 / 1.G AFC Engine On Board Diagnostic Multiport Fuel Injection Service Manual

01-68

Output on GST and/or
on VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0322 / 16706
Ignition/Distributor Engine
Speed Input Circuit No
Signal Malfunction P1339 / 17747
"Crankshaft Pos./Engine Speed
Sensors Cross connected" also in
DTC memory
No
Yes

- 3-pin harness connector on Crankshaft Position
(CKP) sensor -G4- and engine speed (RPM) sensor
-G28- transposed disconnect both connectors and
connect correctly; installation location page 28
-7

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check DTC
memory again
MIL Status:
MIL lights up
immediately
Harness connector for engine
speed (RPM) sensor -G28- loose
or corroded due to moisture in the
harness connector

- Check harness connector for tight fit and contact
corrosion, if necessary reconnect and/or clean,
installation page 28
-7

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check DTC
memory again

Holding socket for engine
speed (RPM) sensor -G28- loose
or -G28- incorrectly adjusted

- Check mounting
- Adjust engine speed bracket page 28
-23

Malfunction cause found: Yes
No
Continued next page

- Erase DTC memory, test drive and check DTC
memory again
Pa
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) - Multi
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)
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yp
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01-70

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0327 / 16711
Knock Sensor 1 Circuit Low
Input (Bank 1 or Single
Sensor) Malfunction P0332 / 16716
"Knock Sensor 2 Circuit Low Input"
Also in DTC memory
No
Yes

- Check knock sensor 1 -G61- and knock
sensor 2 -G66- page 28
-29


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check
DTC memory again
MIL Status:
MIL lights up immediately
Harness connector for Knock Sensor
(KS) 1 -G61- loose or corroded due to
moisture in the harness connector

- Check harness connector for tight fit and
contact corrosion, if necessary reconnect
and/or clean, installation location page 24
-1
For troubleshooting
Display group 015
Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check
DTC memory again

Knock Sensor (KS) 1 -G61- loose

- Check mounting of knock sensor 1 -G61-
and if necessary retighten use insert
3247; tightening torque 20 Nm (15 ft lb)

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check
DTC memory again
Pa
ge 94 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-72

Output on GST and/or
on VAG 1551 scan tool
Possible malfunction cause

Malfunction repair
P0332 / 16716
Knock Sensor 2 Circuit
Low Input (Bank 2) Malfunction P0327 / 16711 "Knock
Sensor 1 Circuit Low Input (Bank 1 or
Single Sensor)" also in DTC memory
No
Yes

- Check knock sensor 1 -G61- and knock
sensor 2 -G66- page 28
-29


Malfunction cause found: Yes
No

- Erase DTC memory, test drive, and after
test drive, check DTC memory again
MIL Status:
MIL lights up
immediately
Harness connector for Knock Sensor
(KS) 2 -G66- loose or corroded due to
moisture in the harness connector

- Check harness connector for tight fit and
contact corrosion, if necessary reconnect
and/or clean, installation location page 24
-
1

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after test
drive, check DTC memory again
For troubleshooting
Display group 016
Knock Sensor (KS) 2 -G66- loose

- Check mounting of knock sensor 2 -G66-
and if necessary retighten use insert 3247;
tightening torque 20 Nm (15 ft lb)

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after test
drive, check DTC memory again
Pa
ge 97 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-74

Output on GST
and/or on VAG 1551
scan tool Possible malfunction cause

Malfunction repair
P0337 / 16721
Crankshaft Position
Sensor Circuit Low
Input Harness connector for Crankshaft Position
(CKP) sensor -G4- loose or corroded due to
moisture in the harness connector

- Check harness connector for tight fit and
contact corrosion, if necessary reconnect
and/or clean, installation location page 28
-7

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after
test drive, check DTC memory again
MIL Status:
MIL lights up
immediately Crankshaft Position (CKP) sensor -G4-
loose or distance to groove on crankshaft
counterweight greater than 1.3 mm (0.053
in.)

- Check crankshaft position sensor -G4- for
correct installation and tight fit

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after
test drive, check DTC memory again

Wiring connection to Crankshaft Position
(CKP) sensor -G4- faulty, or sensor -G4-
faulty

- Check crankshaft position sensor -G4-
page 28
-19


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after
test drive, check DTC memory again
Pa
ge 100 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-76

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0401 / 16785
Exhaust Gas Recirculation
Flow Insufficient Detected EGR system vacuum hose kinked or fallen
off

- Check vacuum hoses

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
MIL Status:
MIL lights up after 2 Trips Leak in a vacuum hose of the EGR system
(e.g. cracked, worn though, etc.)

- Check vacuum hoses for leaks

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again

Vacuum hose between EGR vacuum
regulator solenoid valve -N18- and mechanical
EGR valve plugged

- Check vacuum hoses for
obstructions
For troubleshooting
Display group 017
Malfunction cause found: Yes
No
Continued next page

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
Pa
ge 103 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
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play?action=Goto&t
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e=re
pair&id=AUDI.B5.FU01.01.1

01-78

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0402 / 16786
Exhaust Gas Recirculation
Flow Excessive Detected Vacuum line incorrectly connected
and/or hose connections transposed

- Check EGR system vacuum hose
according to vacuum plan page 24
-111


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after
test drive, check DTC memory again DTC
memory
MIL Status:
MIL lights up after 2 Trips EGR vacuum regulator solenoid
valve -N18- stuck in open position

- Check EGR vacuum regulator solenoid
valve -N18- page 24
-67


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after
test drive, check DTC memory again DTC
memory

EGR valve leaks or is stuck in
open position

- Check mechanical EGR valve page 24
-
70

For troubleshooting Display
group 017
Malfunction cause found: Yes


- Erase DTC memory, test drive and after
test drive, check DTC memory again
Notes:
Pa
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(OBD
) - Multi
port Fuel In
jection
(MFI
)
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-79

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0422 / 16806
Main Catalyst Efficiency
Below Threshold (Bank 1) Are other malfunctions stored in the DTC
memory?

No

Yes

- First correct these malfunctions
according to Diagnostic Trouble Code
(DTC) table.
MIL Status:
MIL lights up after 2 Trips Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again

Bank 1 Three Way Catalytic Converter
(TWC) chemically or thermally aged or
mechanically destroyed

- Replace Three Way Catalytic
Converter (TWC) Bank 1
For troubleshooting
Display groups 035, 036,
044
Malfunction cause found: Yes


- Erase DTC memory, test drive and
after test drive, check DTC memory
again
Note:

With the help of the Oxygen Sensor Probe in front of and behind the Three Way Catalytic Converter (TWC), the rate of
Three Way Catalytic Converter (TWC) deterioration is determined using the Three Way Catalytic Converter (TWC) oxygen
storage capability.
Pa
ge 107 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-80

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0432 / 16816
Main Catalyst Efficiency
Below Threshold (Bank 2) Are other malfunctions stored in the DTC
memory?

No

Yes

- First repair these malfunctions
according to Diagnostic Trouble Code
(DTC) table.
MIL Status:
MIL lights up after 2 Trips Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again

Bank 2 Three Way Catalytic Converter
(TWC) chemically or thermally aged or
mechanically destroyed

- Replace Bank 2 Three Way
Catalytic Converter (TWC)
For troubleshooting
Display groups 035, 036,
044
Malfunction cause found: Yes


- Erase DTC memory, test drive and
after test drive, check DTC memory
again
Note:

With the help of the Oxygen Sensor Probe in front of and behind the Three Way Catalytic Converter (TWC), the rate of
Three Way Catalytic Converter (TWC) deterioration is determined using the Three Way Catalytic Converter (TWC) oxygen
storage capability.
Pa
ge 108 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-81

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0440 / 16824
Evaporative Emission
Control System Malfunction Evaporative emissions system hoses
kinked or pinched

- Check hoses for correct fit

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
MIL Status:
MIL lights up after 2 Trips Leak in the EVAP system between
Intake manifold and EVAP canister
purge regulator valve -N80- or
EVAP canister purge regulator valve -
N80- and sensor for EVAP canister -
G172- or
Sensor for EVAP canister -G172- and
EVAP canister
- Check EVAP system for leaks

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
Pa
ge 109 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-83

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0452 / 16836
Evaporative Emission
Control System Pressure
Sensor Low Input Harness connector on sensor for EVAP
canister -G172- (differential pressure sensor)
loose or corroded due to moisture in the
harness connector

- Check harness connector for tight fit
and contact corrosion, if necessary
reconnect and/or clean

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
MIL Status:
MIL lights up immediately Wiring connection to sensor for EVAP
canister -G172- (differential pressure sensor)
faulty, or sensor -G172- faulty

- Check sensor for EVAP canister -
G172- (differential pressure sensor)
page 24
-61


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
after test drive, check DTC memory
again
For troubleshooting
Display group 030
Engine Control Module (ECM) -J192- faulty

- Replace and code engine control
module page 01
-265
erase DTC
memory and test drive check DTC
memory
Note:
The malfunction "P0542 / 16836" is set as soon after engine start as the differential pressure sensor signal is less than 0.1 V
Pa
ge 111 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1