air condition AUDI A6 1995 C5 / 2.G AHA Engine Multiport Fuel Injection And Ignition System Workshop Manual

24-17

Test conditions

Fuses for engine electronics OK
No malfunctions stored in DTC memory
page 01
-16


Engine Coolant Temperature (ECT) at least
80 C (176 F)

All electrical consumers switched off
(radiator coolant fan must not run during
test)
A/C switched off
Exhaust system free of leaks
Automatic transmission selector lever in "P"
or "N" position
Throttle valve in Closed Throttle Position
(CTP); for Accelerator Pedal (AP) cable
adjustment Repair Manual, Fuel Supply
System, Repair Group 20
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Wiring diagram

Test conditions
Engine Coolant Temperature (ECT) at least
80 C (176 F)
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24-26

Continuation
If the value in either display field 1 or 3 is NOT
OK, or if the value does not fluctuate by at least 2
%:

- Road test to condition oxygen sensor(s)
(eliminate possible contamination) and repeat
test.
If the value in either display field 1 or 3 is still
NOT OK, or if it still does not fluctuate by at least
2 %:

- Check Oxygen Sensor (O2S) heater(s) page
24
-34
.
If the value in either display field 1 or 3 remains
constant:

- Check oxygen sensor voltage(s) (display fields 2
and 4).

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

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24-45

Continuation

- Road test to condition oxygen sensor (eliminate
possible contamination) and repeat test.
If the values are still NOT OK:

- Check Oxygen Sensor (O2S) heater(s) page
24
-52
.

- Briefly accelerate engine over 3000 RPM.
If the value in either display field 1 or field 3
remains constant:
page Page 24
-46
, Evaluation of display group
36.
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24-62

Continuation
If displayed value is NOT OK (not as specified):

- Road test to condition oxygen sensor (eliminate
possible contamination) and repeat test.
If displayed value is still NOT OK:

- Replace HO2S -G39-.

- Check readiness code page 01
-70
. If
Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code page 01
-73
.
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24-65

Continuation
If displayed value is NOT OK (not as specified):

- Road test to condition oxygen sensor (eliminate
possible contamination) and repeat test.
If displayed value is still NOT OK:

- Replace HO2S -G108-.

- Check readiness code page 01
-70
. If
Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code page 01
-73
.
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24-66

Engine operating conditions (engine
electronics), checking


Note:
This test checks whether the Motronic Engine
Control Module (ECM) -J220- recognizes the
engine operating conditions.

Required special tools and test equipment

VAG1551 or VAG1552 scan tool with
VAG1551/3 adapter

Test requirements
Engine oil temperature at least 80 C (176
F)

Checking

- Connect VAG1551 or VAG1552 scan tool and
press buttons -0- and -1- to insert "Engine
Electronics" address word 01 (with engine
running at idle) page 01
-8 .
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.
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24-67

- Check engine operating conditions (display field
4):

Display fields

1 2 3 4
Display group 5: Engine electronics-operating conditions
Display xxx RPM xx.xx ms xxx km/h Idle
Part throt
Full throt 1)
Decel
Enrich
Indicates Engine speed
(in 40 RPM steps) Engine load Vehicle speed Operational condition
Range 0 - 6800 RPM 0.00 - 12.75 ms --- ---
Specified value 620 - 740 RPM
(all-wheel drive)
or
740 - 860 RPM
(front-wheel drive) 1.00 - 2.50 ms 0 km/h Idle: "Idle"
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24-116

Evaporative Emissions (EVAP) canister
purge regulator valve, checking


WARNING!

Whenever carrying out work on the fuel
supply and/or fuel injection systems, read
and carefully follow the Cautions, Warnings,
and rules of cleanliness page 24-9 .

Note:
Component locations page 24
-1

Required special tools and test equipment

VAG1551 or VAG1552 Scan Tool (ST) with
VAG1551/3 adapter cable

Test conditions
Engine coolant temperature at least 80 C
(176 F)

Function check

- Connect VAG1551 or VAG1552 scan tool and
press buttons -0- and -1- to insert "Engine
Electronics" address word 01 (with engine
running at idle) page 01
-8 .
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24-118


Display fields

1 2 3 4
Display group 70: EVAP canister purge regulator valve
Display xxx % xx.x % xx.xx g/s Test OFF/Test
ON
EVAP OK
EVAP n.OK
Indicated EVAP canister purge regulator
valve duty cycle during diagnosis Oxygen sensor deviation
during diagnosis Idle Air Control (IAC) valve
deviation during diagnosis Diagnosis
condition
Diagnosis
results
Range 0 - 100 % -25.0 to +25.0 % -2.70 to +4.16 g/s ---
Specified
value 0 - 93 % - 15.0 to +15.0 % 1.00 - 0.00 g/s EVAP OK If "EVAP n.OK" is indicated in display field 4:

- Check for blockage or leaks page 24
-119
.
If "EVAP OK" is indicated in display field 4:

-
Press button.Rapid data transfer
HELP

Indicated on display
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yp
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