1999 AUDI A4 engine

2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is
recognized after the engine has been restarted. Significance of MIL Page 01
-3 .
Pa
ge 34 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-29

DTC
Description of
malfunction
Corrective action
SAE
VAG


P0421 16805 Warm Up Catalyst,
Bank 1
Efficiency Below
Threshold
2) Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Repair Group 26;
Components of Exhaust system removing and installing, Catalytic converter
removing and installing - Generate readiness code Page 01
-99
, if same DTC is displayed again, replace
warm up catalytic converter bank 1
P0431 16815 Warm Up Catalyst,
Bank 2
Efficiency Below
Threshold
2) Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Repair Group 26;
Components of Exhaust system removing and installing, Catalytic converter
removing and installing - Generate readiness code Page 01
-99
, if same DTC is displayed again, replace
warm up catalytic converter bank 1
2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is
recognized after the engine has been restarted. Significance of MIL Page 01
-3 .
Important note:
The warm up catalytic converters are located between the two oxygen sensors of the relevant cylinder bank. The warm up
catalytic converters (little smaller than main catalytic converter) are located closer to the engine, not to be misunderstood with
the main catalysts you see immediately once the vehicle is lifted.
Pa
ge 35 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-30

DTC
Description of
malfunction
Corrective action
P0441 16825 EVAP Emission Contr.
Sys. Incorrect
Purge Flow
2) - Check EVAP canister purge regulator valve, perform output Diagnostic Test
Mode (DTM) Page 01
-75

P0442 16826 EVAP Emission Contr.
Sys. (Small Leak)
Leak Detected
2) - Check EVAP system and tank system for leaks
P0455 16839 EVAP Emission Contr.
Sys. (Gross Leak)
Leak Detected Repair Manual, Fuel Supply System, Repair Group 20, Components of EVAP
system servicing, carry out tank leak test

P0456 16840 Tank ventilation system
Pin-hole leak detected
Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Repair Group 20;
Fuel supply, gas engine; EVAP canister system components, servicing; tank leak diagnostic, performing.
- Checking fuel supply and ventilation systems for leaks
2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is
recognized after the engine has been restarted. Significance of MIL Page 01
-3 .
Pa
ge 36 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

Diagnostic for Cruise Control System

2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is
recognized after the engine has been restarted. Significance of MIL Page 01
-3 .
Pa
ge 38 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-32

DTC
Description of malfunction
Corrective action
SAE
VAG


P0601 16985 Internal Contr. Module Memory
Check Sum Error
2) - Replace Engine Control
Module (ECM) Page 24
-24
P0604 16988 Internal Contr. Module Random Access
Memory (RAM) Error
2)
P0605 16989
Internal Contr. Module ROM Test Error
2)

P0606 16990 Control module faulty
- Replace Engine Control Module (ECM) Page 24
-24
2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is
recognized after the engine has been restarted. Significance of MIL Page 01
-3 .
Pa
ge 39 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-33

DTC
Description of malfunction
Corrective action
SAE
VAG


P1102 17510 O2 Sensor Heating Circ., Bank1-
Sensor1
Short to B+
2) - Check oxygen sensor heater Page 24
-114
P1105 17513 O2 Sensor Heating Circ., Bank1-
Sensor2
Short to B+
2)
P1107 17515 O2 Sensor Heating Circ., Bank2-
Sensor1
Short to B+ 2)
P1110 17518 O2 Sensor Heating Circ., Bank2-
Sensor2
Short to B+ 2)
P1111 17519 O2 Control (Bank 1)
System too lean - Check oxygen sensor adaptation values and oxygen sensor control
Page 24
-86

P1112 17520 O2 Bank 1
System too rich
2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is
recognized after the engine has been restarted. Significance of MIL Page 01
-3 .
Pa
ge 40 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

recognized after the engine has been restarted. Significance of MIL Page 01
-3 .
Pa
ge 42 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-35

DTC
Description of malfunction
Corrective action
SAE
VAG


P1119 17527 O2 Sensor Heater Circ., Bank2-Sensor1
Short to Ground
2) - Check oxygen sensor heater Page 24
-114
.
P1120 17528 O2 Sensor Heater Circ., Bank2-Sensor1
Open
2)
P1121 17529 O2 Sensor Heater Circ., Bank2-Sensor2
Short to Ground
2)

P1122 17530 O2 Sensor Heater Circ., Bank2-Sensor2
Open
2)

2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is
recognized after the engine has been restarted. Significance of MIL Page 01
-3 .
Pa
ge 43 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1