fuel cap AUDI A4 2000 B5 / 1.G AFC Engine On Board Diagnostic Multiport Fuel Injection Workshop Manual

(OBD) capability, the engine control module is faulty Diagnostic
Trouble Code (DTC) table, page 01
-26
.
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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.
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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.
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(MFI
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01-150

Basic Setting (scan tool function 04)


Notes:

Basic setting is carried out with engine
running.
The OBD II engine control module shows the
"Readiness Code" in display group 29. The
readiness code is reset when the engine control
module power is off and each time the DTC
memory is erased. In order to regenerate the
readiness code it is necessary to take a trip in
"mixed city and highway" driving-approx. 1-1/2
to 5 minute drive at 80-100 km/h (50-63 mph)
with manual transmission in 4th or 5th gear,
preferably 4th gear, or automatic transmission
selector lever in "D" position.
When the "Basic Setting" function 04 is initiated
with the VAG 1551 scan tool, the learning
values are relearned in systems capable of
learning. Learning is prohibited, as soon as a
malfunction is stored in the DTC memory that
relates to a system capable of learning (not with
sporadic malfunctions).
All learning values are erased by disconnecting
the connector from the Engine Control Module
(ECM). After that, uneven idle can occur briefly.
In this case, let engine run in idle for a few
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01-214
Notes on display field 2:

The display values are set to "0" at each start, since the function capability of components and systems that can affect the
exhaust are checked again and again.
Leak testing of the EGR system is only carried out after a preceding cold start (water temperature -10 C to 30 C (14 to
86 F). Value "0" = Diagnosis not carried out yet
Value "1" = Diagnosis carried out
X
X
X
X
X
X
X
X
Meaning of 8-digit "Trip Status" display

1 = Three way catalytic converter diagnosis, banks 1 and 2
(for diagnostic conditions display group 044)
2 = Exhaust Gas Recirculation (EGR) system leak testing

3 = Evaporative Emissions (EVAP) throughput diagnosis
(for diagnostic conditions display group 030)
4 = Secondary air injection system throughput and leak testing
(always "0" on vehicles without secondary air injection system; for diagnostic conditions
display groups 020 and 021)
5 = Oxygen sensor control diagnosis
Pa
ge 304 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