light AUDI A4 1997 B5 / 1.G AFC Engine On Board Diagnostic Multiport Fuel Injection Workshop Manual

01-2
On Board Diagnostic (OBD) II technical data

Memory

Permanent memory (If the engine control module is disconnected from the permanent battery positive voltage (B+) supply,
the Diagnostic Trouble Code (DTC) memory and "Readiness Code" will be erased.)
Data output
Rapid data transfer
Additional malfunction display by Malfunction Indicator Light (MIL) lighting up
Address words
Address word 00: Automatic Test Sequence Switch ignition on or let engine idle
Address word 01: Engine Electronics Switch ignition on or let engine idle
Address word 33: OBD II Switch ignition on or let engine idle
Functions under address word 01:
Function
01: Check Control Module
Versions Switch ignition on or let engine idle
Function
02: Check DTC Memory Let engine idle, or, crank engine with starter for at least 5 sec. without
switching ignition off
Function
03: Output Diagnostic Test
Mode Switch ignition on
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01-4

Malfunction Indicator Lamp (MIL),
functions


Functional testing:
The Malfunction Indicator Lamp (MIL) must light up every time the
ignition is switched on and go out after the engine starts. If a
malfunction is recognized by the engine control module or the
transmission control module, this is indicated by the MIL lighting up. If the MIL lights up continuously, there is a malfunction present that
makes the exhaust gas worse. In this case, the DTC memory for the
engine control module and/or the transmission control module should
be checked. If the MIL starts to blink, there is a malfunction that can lead to
damage of the three way catalytic converter (e.g. combustion misfiring
with high misfiring rate). In this case, driving should only continue with
reduced power (until the MIL goes off or lights up continuously) and
the malfunction should be eliminated as quickly as possible.
- Switch ignition on: the MIL must light up. If the MIL does not light up,
check wiring according to wiring diagram and/or replace lamp.
- Start engine and let idle: MIL must go out after a couple seconds. If the
MIL does not go out after the engine starts, check DTC memory for the
engine and/or transmission control modules (malfunctions in DTC
memory).
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01-5
Malfunction recognition and repair

Notes:

Before initiating the On Board Diagnostic (OBD) program, and before testing wiring and replacing components, check the
following ground connections for corrosion and damaged connections and repair them if necessary
- Check ground connections on intake manifold
- Battery ground strap OK
- Ground cable between engine and body OK Malfunction recognition and repair is described for the VAG 1551 scan tool, since it offers significantly more functions.
However, malfunction recognition and repair is also possible with a "generic" scan tool.
A specific procedure must be used to evaluate malfunctions, since the engine electronics can be checked with address
word 01 and address word 33 on OBD II vehicles. Address word 33 can only be used to check malfunctions that have
already switched on the Malfunction Indicator Light (MIL). Address word 01 can also display the malfunctions that have
not switched on the MIL. In contrast to before, the MIL is not switched on immediately with some malfunction types, but
only after two successive trips with cold starts preceding them where the malfunction occurs. If there is a customer
complaint and/or driving performance problem, the DTC memory should be checked thoroughly with address word 01,
function 02. On vehicles with MIL lit up, the DTC memory should also be checked with address word 33, mode 3. If the
DTC memory is checked with mode 3, mode 2 should also be checked which shows the operating conditions as they were
when the malfunction was recognized.
If a malfunction is present for longer than a specified time, the malfunction is stored as a static malfunction. Malfunctions
that never or immediately switch the MIL on are set as "sporadic" at each engine start. If the malfunction occurs again, the
"sporadic" status is erased again. The "sporadic" status is erased exclusively after an OK diagnosis for malfunctions that
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01-9

For the function:

02: Check DTC
Memory - Let engine idle, or, crank
engine with starter for at
least 5 seconds without
switching ignition off
03: Output
Diagnostic
Test Mode - Switch ignition on
04: Basic Setting
- Let engine run or switch
ignition on
07: Code Control
Module - Switch ignition on
08: Read
Measuring
Value Block - Let engine run or switch
ignition on

- Switch printer on with PRINT button (indicator
light in the button lights up).

- Press button -1- for "rapid data transfer"
operating mode.
Rapid data transfer
HELP
Insert address word XX

Indicated on display
Note:
After inserting address word 00 and pressing -Q- button to confirm input,
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01-26
Diagnostic Trouble Code (DTC) table


Following are all the possible malfunctions that can be recognized by the Engine Control Module (ECM) -J192- and
printed on the VAG 1551 scan tool printer, listed according to code identifier ( SAE and VAG codes).
Malfunctions that switch the MIL on never or immediately are set as "sporadic" each time the engine is started. If the
malfunction occurs again, the "sporadic" status is set again. For malfunctions that only switch the MIL on after two trips
with malfunction, the "sporadic" status is only erased after an OK diagnosis.
If the MIL lights up with engine running, there is a malfunction that makes the exhaust gas worse. If the MIL lights up and
the engine is running, there must in any case be a malfunction stored in the DTC memory of the engine control module
and/or of the transmission control module. In this case, the DTC memory of the engine control module and/or the
transmission control module must be checked.
If the MIL starts to blink, there is a malfunction present that can lead to three way catalytic converter damage (e.g.
combustion misfiring with high misfiring rate). In this case, the trip should be continued with reduced power (until the MIL
goes out or lights up continuously) and the malfunction should be eliminated as quickly as possible.
The malfunction is not stored in the DTC memory immediately and the MIL is not switched on immediately with some
malfunction types, but only after two successive trips with or without preceding cold start (-10 to 30 C (14 to 86 F)
and malfunction occurring (malfunction recognition twice). The MIL switching condition is always specified in the Diagnostic Trouble Code (DTC) table.
Combustion misfiring with high misfiring rate is displayed immediately with the MIL blinking, since the three way catalytic
converters can be damaged. In this case, driving should continue only with reduced power and the malfunction should be
eliminated as soon as possible.
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01-27

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

Malfunction repair
P0102 / 16486
Mass or Volume Air Flow
Circuit Low Input Harness connector on Mass Air Flow
(MAF) sensor -G70- loose or corrosion
because of 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, after test
drive check DTC memory again
MIL Status:
MIL lights up immediately Wiring connection to Mass Air Flow (MAF)
sensor -G70- faulty or sensor -G70- faulty

- Check Mass Air Flow (MAF) sensor -
G70- page 24
-81


Malfunction cause found: Yes
No

- Erase DTC memory, test drive, after test
drive check DTC memory again
For troubleshooting
Display groups 000, 001,
019
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 "P0102 / 16486" is set as soon as the signal voltage drops below 0.5 volts for longer than 0.3 sec (engine
speed under 2000 RPM).
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01-28

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

Malfunction repair
P0103 / 16487
Mass or Volume Air Flow
Circuit High Input Harness connector on Mass Air Flow
(MAF) sensor -G70- loose or corroded due
to dampness in the harness connector

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

Malfunction cause found: Yes
No

- Erase DTC memory, test drive, after test
drive check DTC memory again
MIL Status:
MIL lights up immediately Wiring connection to Mass Air Flow
(MAF) sensor -G70- faulty or sensor -G70-
faulty

- Check Mass Air Flow (MAF) sensor -
G70- page 24
-81


Malfunction cause found: Yes
No

- Erase DTC memory, test drive, after test
drive check DTC memory again
For troubleshooting
Display groups 000, 001,
019
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 "P0103 / 16487" is set as soon as the signal voltage rises above 5 volts for longer than 0.5 sec (engine
speed below 2000 RPM).
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01-29

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

Malfunction repair
P0116 / 16500
Engine Coolant Temperature
Circuit Range/Performance
Problem Harness connector on Engine Coolant
Temperature (ECT) sensor -G62- loose or
corroded due to dampness 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, after
test drive check DTC memory again
MIL Status:
MIL lights up immediately Wiring conection to Engine Coolant
Temperature (ECT) sensor -G62- faulty,
or sensor -G62- faulty

- Engine Coolant Temperature (ECT)
sensor -G62-, checking page 28
-25


Malfunction cause found: Yes
No

- Erase DTC memory, test drive, after
test drive check DTC memory again
For troubleshooting Display
groups 000, 001
Engine Control Module (ECM) -J192-
faulty

- Replace and code engine control
module page 01
-265
erase DTC
memory and test drive check DTC
memory
Notes:
The malfunction "P0116 / 16500" is set as soon as the coolant temperature lies under 55 C (131 F) after engine start, but
18 minutes later the temperature has not risen to over 70 C (158 F).
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01-30

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

Malfunction repair
P0117 / 16501
Engine Coolant
Temperature Circuit
Low Input Harness connector on Engine Coolant
Temperature (ECT) sensor -G62- loose or
corroded due to dampness 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, after test
drive check DTC memory again
MIL Status:
MIL lights up
immediately Wiring connection to Engine Coolant
Temperature (ECT) sensor -G62- faulty, or
sensor -G62- faulty

- Engine Coolant Temperature (ECT)
sensor -G62-, checking page 28
-25


Malfunction cause found: Yes
No

- Erase DTC memory, test drive, after test
drive check DTC memory again
For troubleshooting
Display groups 000,
001
Engine Control Module (ECM) -J192-
faulty

- Replace and code engine control module
page 01
-265
erase DTC memory and
test drive check DTC memory
Notes:
The malfunction "P0117 / 16501" is set as soon as the signal voltage drops below 0.10 volts for longer than 1 sec when
ignition is switched on (corresponds to a coolant temperature over 200 C (392 F).
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01-31

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

Malfunction repair
P0118 / 16502
Engine Coolant
Temperature Circuit
High Input Harness connector on Engine Coolant
Temperature (ECT) sensor -G62- 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 check
DTC memory again
MIL Status:
MIL lights up
immediately Wiring connection to Engine Coolant
Temperature (ECT) sensor -G62- faulty, or
sensor -G62- faulty

- Check Engine Coolant Temperature
(ECT) sensor -G62- page 28
-25


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check
DTC memory again
For troubleshooting
Display groups 000,
001
Engine Control Module (ECM) -J192-
faulty

- Replace and code engine control module
page 01
-265
erase DTC memory and
test drive check DTC memory
Notes:
The malfunction "P0118 / 16502" is set as soon as the signal voltage is over 4.98 volts for longer than 1 sec with ignition on
(corresponds to a coolant temperature below -50 C (-58 F)).
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