engine AUDI A4 1996 B5 / 1.G AFC Engine On Board Diagnostic Multiport Fuel Injection Workshop Manual

01-199
Display group 017
Note:
If in display group 029, display field 1, the value of the EGR system throughput diagnosis is not set to "0" during the
regeneration of the "readiness code," and/or a malfunction relating to the exhaust system is stored in the DTC memory,
display group 017 is used to carry out a selective diagnosis.
During cold start at idle, -10 C to 30 C (14 to 86 F), and during "Basic Setting" function 04, no exhaust gas recirculation
takes place. Since exhaust gas recirculation is switched off automatically during "Basic Setting" function 04, diagnosis of EGR
throughput is evaluated only in "Read Measuring Value Block." function 08. If diagnostic conditions are fulfilled, the Engine Control Module (ECM) checks the flow through the EGR system after each
start. The diagnostic conditions are only reached during a trip at 80-100 km/h (50-63 mph) in 4th or 5 gear and/or with selector
lever in the "D"position, preferably in 4th gear position. If the diagnostic conditions are fulfilled, the diagnosis is active. In order
to get a diagnostic result, the vehicle must be driven approx. 1-1/2 to 5 minutes under the diagnostic conditions. However, the
diagnosis is only considered OK when the EGR temperature (display field 4) is greater than 50 C (122 F) during the reading
time (display field 2). Diagnosis of the EGR flow (exhaust gas recirculation quantity) is active as soon as the following diagnostic conditions are
fulfilled:

Coolant temperature: greater than 8 C (46 F) ( display group 001) Vehicle speed: constant drive
Engine speed: 2000-3000 RPM ( display group 003) Engine load: 30-60%
Pa
ge 280 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

01-200

Display shows
Specified display value
Designation
Basic setting 17
1 2 3 4 0 - 1 1 = Timer 1 (final value = 1)
0 - 225 2 = Timer 2 (final value = 48 or 160)
30% - 60% 3 = Momentary engine load

0C - 255C
4 = Exhaust gas recirculation temperature (EGR temperature sensor -G98-)
Notes on display fields 1 and 2:

In display fields 1 and 2, the timers are displayed. The final value of timer 2 is "48" or "160". The final values "48" and
"160" are reading times ("48" = reading time 1; "160" = reading time 2).
If the diagnostic conditions are fulfilled, the timers are incremented, outside the diagnostic conditions they are
decremented.
Counter 1 is incremented by "1" as soon as counter 2 reaches the value "255." If the value 255 is reached, counter 2 goes
back to "0" and starts to increment again up to "48" (reading time 1).
If reading time 1 has been reached, the Engine Control Module (ECM) -J192- checks the EGR temperature (display field
4). If the EGR temperature is greater than 50 C (122 F), the diagnosis is OK and the diagnostic program is discontinued.
If the EGR temperature during reading time 1 is less than 50 C (122 F),counter 2 counts up to "160"(reading time 2). When reading time 2 is reached, the -J192- checks the EGR temperature (display field 4) again. If the EGR temperature is
now greater than 50 C (122 F), the diagnosis is OK and the diagnostic program will be discontinued. If the EGR
temperature is again less than 50 C (122 F), the EGR flow test is carried out again.
Pa
ge 281 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

If the EGR flow test is to be carried out selectively or after an OK diagnosis, stop the engine and start it again.
Pa
ge 282 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

01-201
Display group 018 Display
shows Specified display
value Designation
Basic setting
18
1 2 3 4 __ % 1 = Internal duty cycle (triggering) - Idle Air Control (IAC) valve -N71-
_.___ A 2 = Idle Air Control (IAC) valve -N71- current
-40 to +60% 3 = Power control from Idle Air Control (IAC) valve -N71-
12,000 - 14,000 V 4 = Engine Control Module (ECM) -J192- voltage supply (battery voltage) display
group 001, display field 1 Note on display field 1:
The internal calculation value in the engine control module for the duty cycle is displayed without power and voltage
correction.
Note on display field 2:
The actual power draw by the Idle Air Control (IAC) valve -N71- is displayed.
Note on display field 3:

Positive values indicate increase in the duty cycle, in order to reach the specified current.
Negative values indicate a decrease in the actual duty cycle to reach the specified current.
Pa
ge 283 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

01-202
Display group 019 Display shows
Specified display value
Designation/diagnose
Basic setting 19
1 2 3 4 At idle: 1.5 - 3.5% 1 = Momentary engine power (internal computation value)
At 2500 RPM:
6.5 - 9.5%
At idle:
3.0 - 5.5 g/s 2 = Intake air quantity (via mass air flow sensor)
At 2500 RPM:
9.5 - 13.5 g/s
___ km/h 3 = Momentary vehicle speed display group 003, display field 4 _._ m/s 4 = Fuel injection time (average of all cylinders) Note on display field 1:
The momentary engine power is a control module-internal calculated value that is calculated from the amount of air taken in
under normal conditions (air pressure 1013 mbar, air temperature 20 C or 68 F).
Pa
ge 285 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

01-204
Display group 022
Notes:
Display group 022 should only be considered on vehicles with traction control (ATC).
Vehicles with traction control (ATC) can be recognized by the ATC indicator light in the instrument cluster and/or ABS (ATC)
On Board Diagnostic (OBD).
Repair Manual, Brake System On Board Diagnostic (OBD), Repair Group 01.

The wheel slip information for traction control (ATC) is calculated in the ABS control module. If slip is recognized, the ABS
control module requests a reduction in torque from the Engine Control Module (ECM). This torque reduction is divided into 12
reducing stages.
With a cold engine, coolant temperature less than 20 C (68 F), the reduction of engine torque is obtained:
With retarded ignition timing angle for lower reducing stages (1-5)
By brief shut-off of individual fuel injectors for higher reducing stages (6-12)
If the engine is warm, coolant temperature greater than 40 C (104 F), the engine torque reduction is obtained only by briefly
switching off individual fuel injectors.
Display shows
Display/specified value
Designation
Basic setting 22
1 2 3 4 0 - 12 1 = Reducing stages

_._ crankshaft
2 = Ignition timing point retarded by ATC (only with cold engine)
Pa
ge 287 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

-68 Nm to 250 Nm 3 = Reduced engine torque (actual moment)
-68 Nm to 250 Nm 4 = Unreduced engine torque
Pa
ge 288 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

01-207
Note on display field 3: X
X
Meaning of the 2-digit display:

1 = A/C compressor off/on (0 = off; 1 = on)
Notes:

On vehicles without A/C "0" is always displayed.
Check A/C compressor page 24
-90
.
The A/C compressor is shut off for approx. 12 sec. by -J192- when accelerating from a stop and from low speed.
If the gas pedal is released sooner, the time is reduced to a minimum of 3 sec. At wide open throttle, the A/C
compressor is switched off by the automatic transmission (kick-down switch).

2 = Rear window heating - Signal (0 = off; 1 = on)
Notes:
The rear window heating signal is only displayed on vehicles without A/C.
On vehicles with A/C "0" is always displayed.
Check rear window heater signal page 24
-88
.
Notes on display field 4:

If the A/C compressor is off display field 3; display field 4 can be used to recognize whether the compressor was
switched off by the engine control module. Meaning of the 1-digit display:
Pa
ge 292 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

X
Meaning of 1-digit display

Value "0" = A/C compressor not switched off by engine control module
Value "1" = A/C compressor switched off by engine control module
Pa
ge 293 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

01-209
Display group 027 Display
shows Display specified
value Designation/diagnosis
Basic setting
27
1 2 3 4 X 1 = Malfunction Indicator Lamp (MIL) wire from Transmission Control Module
(TCM)
X 2 = Fuel level signal from instrument cluster
0.000 V 3 = ---------------
0.000 V 4 = --------------- Notes on display field 1:

On vehicles with manual transmission, "1" is always displayed.
Checking Malfunction Indicator Lamp (MIL) wire from transmission control module page 24
-105
.
X
Meaning of the 1-digit display:

Value "0" = ignition on, engine not running
Value "1" = engine running Note on display field 2:

Check fuel level signal from instrument cluster page 24
-107
.
Pa
ge 296 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