display AUDI A6 1998 C5 / 2.G AEB Engine Motronic MFI And Ignition System

24-12

Checking

- Connect VAG 1551 or VAG 1552 scan tool and
press buttons -0- and -1- to insert "Engine
Electronics" address word 01 (with engine
running at idle) Page 01
-7 .
Rapid data transfer
HELP
Select function XX

Indicated on display
- Press buttons -0- and -4- to select "Basic Setting" function 04, and
press -Q- button to confirm input.
System in Basic Settin
g
HELP
Input displa
y group number XXX

Indicated on display
- Press buttons -0-, -0- and -1- to input display group number 1, and
press -Q- button to confirm input.
System in Basic Setting 1 1 2 3 4

Indicated on display (1-4 = display fields)
Note:
After selecting function 04, the ECM initiates the following:
Continue with the test only when the operating conditions in display field 4
are satisfied.
EVAP canister purge regulator valve is closedA/C compressor is switched of
f
-
Briefly raise engine speed (acceleration burst) and let engine run at idle
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24-13

- Compare display with specified values (display
fields 1-4):

Display fields

1 2 3 4
Display group 1: Engine idle speed
Display xxxx RPM
xxx.x C
xx.x% xxxxxx
Indicates Idle speed Engine Coolant
Temperature (ECT) Oxygen sensor control Adjustment
conditions
Range 0-6800 RPM
(in 40 RPM steps) --- -25.0 to 25.0 % ---
Specified
value 760-960 RPM
80.0 -105.0 C
In the range from -10.0 to 10.0 %,
the value must change by at least
2 % 111111

If not as specified Page 24
-99
,
Throttle valve control module,
checking
--- If not as specified Page 24
-99
,
Throttle valve control module,
checking
Explanation
Page 24
-15

If displayed values are OK (as specified):

- Press -C- button.

- Press buttons -0-, -5- and -6- to input display
group number 56, and press -Q- button to
confirm input.
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yp
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System in Basic Setting 56 1 2 3 4

Indicated on display (1-4 = display fields)
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) and i
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play?action=Goto&t
yp
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pair&id=AUDI.B5.FU02.24.1

24-14

- Compare display with specified values (display
fields 1-4):
Display fields

1 2 3 4 Display group 56: Engine idle speed
Display xxxx RPM xxxx RPM x.xx g/s xxxx
Indicates Engine speed
(actual) Engine
speed
(specified) Mass air flow
(idle speed control) Operating
conditions
Range 0-2550 RPM
(steps of 10 RPM) --- -2.80 to 4.17 g/s ---
Specified
value 820-900 RPM 860 RPM -1.11 to 1.11 g/s 0000

If not as specified Page 24
-99
,
Throttle valve control module,
checking
--- If not as specified Page 24
-99
,
Throttle valve control module,
checking
Explanation
Page 24
-16


-
Press button to advance program
sequence.
- Press buttons -0- and -6- to select "End Output"
function 06, and press -Q- button to confirm
input.
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yp
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24-15
Evaluation of 6-digit display:

"1" = Adjustment conditions fulfilled
"0" = Adjustment conditions not fulfilled
If adjustment conditions have been fulfilled (indicated in display field 4), a series of 6 numerals ("1") will be displayed. If
one of the digits in the 6-digit display is "0," the adjustment condition has not been fulfilled. Repair the cause of the
unfulfilled condition, and repeat the test.
Explanation (display = 1)
x
x
x
x
x
x
Adjusting conditions (display group 1)
1
Engine Coolant Temperature (ECT) above 80 C
1 Engine speed less than 2000 RPM
1 Throttle valve closed
1 Oxygen sensor control active
1 Closed Throttle Position (CTP) switch closed
1 A/C compressor off
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pair&id=AUDI.B5.FU02.24.1

24-16
Evaluation of 4-digit display:
Explanation (display = 0)
x
x
x
x
(Display group 56)
0 A/C compressor off ("0" = off; "1" = on)
0 Transmission selector lever in "P" or "N" position ("0" = "P" or "N" position; "1" = 2/3/4/R/D)
0 Not used ("0" is always displayed)
0 Not used ("0" is always displayed)
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yp
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pair&id=AUDI.B5.FU02.24.1

24-18

Checking

- Connect VAG 1551 or VAG 1552 scan tool and
press buttons -0- and -1- to insert "Engine
Electronics" address word 01 (with engine
running at idle) Page 01
-7 .
Rapid data transfer
HELP
Select function XX

Indicated on display
- Press buttons -0- and -8- to select "Read Measuring Value Block"
function 08, and press -Q- button to confirm input.
Read Measurin
g Value Block
HELP
Input displa
y group number XXX

Indicated on display
- Press buttons -0-, -3- and -2- to input display group number 32, and
press -Q- button to confirm input.
Read Measuring Value Block 32 1 2 3 4

Indicated on display (1-4 = display fields)
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24-19

- Check oxygen sensor control learning values
(display fields 1 and 2):

Display fields

1 2 3 4
Display group 32: Oxygen sensor control learning values
Display xx.x % xx.x %
Indicates Oxygen sensor control learning value at idle
(additive)
(before TWC) Oxygen sensor control learning value at partial load
(multiplicative)
(before TWC)
Range -26.0 to 26.0 % -25.0 to 25.0 %
Specified
value -8.0 to 8.0 %
(can vary slightly) -8.0 to 8.0 %
(can vary slightly)
If not as specified Page 24
-22
, Evaluation of display group 32

If displayed values are OK (as specified):

- Press -C- button.

- Press buttons -0-, -3- and -3- to input display
group number 33, and press -Q- button to
confirm input. Read Measuring Value Block 33

Indicated on display (1-4 = display fields)
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p://127.0.0.1:8080/audi/servlet/Dis
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24-20

- Check oxygen sensor control (display fields 1
and 2):

Display fields

1 2 3 4
Display group 33: Oxygen sensor control
Display xx.x % x.xxx V
Indicates Oxygen sensor control
(before TWC) Oxygen sensor voltage
(before TWC)
Range -25.0 to 25.0 % 0.000-1.000 V
Specified
value Within the range from -10.0 to 10.0 %
the value must change by at least 2 % Within the range from 0.000 to 1.000 V the value must
fluctuate at least 30 times per minute, and change by at
least 0.3 volts

If not as specified Page 24
-21
,
Continuation
If not as specified Page 24
-23
, Evaluation of display
group 33

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24-21

Continuation
If the value in display field 1 is NOT OK, or if the
value does not fluctuate by at least 2 %:

- Road test to condition oxygen sensor (eliminate
possible contamination) and repeat test.
If the value in display field 1 is still NOT OK, or if
it still does not fluctuate by at least 2 %:

- Check Oxygen Sensor (O2S) heater Page 24
-
27
.
If the value in display field 1 remains constant:

- Check oxygen sensor voltage (display field 2).

-
Press button to advance program
sequence.
- Press buttons -0- and -6- to select "End Output"
function 06, and press -Q- button to confirm
input.

- Switch ignition off.
Pa
ge 31 of 135 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/19/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU02.24.1