light AUDI A4 1997 B5 / 1.G AFC Engine On Board Diagnostic Multiport Fuel Injection Service Manual
Page 92 of 366
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
ge 92 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 
Page 94 of 366
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
)
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 
Page 97 of 366
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
)
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 
Page 100 of 366
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
)
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 
Page 103 of 366
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
)
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 
Page 105 of 366
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
ge 105 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 
Page 107 of 366
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
)
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 
Page 108 of 366
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 
Page 109 of 366
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 
Page 111 of 366
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