Page 17 of 166
13.5-15.5 ohms ( )
1) Engine at room temperature; with the engine at normal operating temperature the resistance increases by approx. 4-6
ohms.
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Page 18 of 166

24-14
Fuel injection system, servicing
Servicing ignition system page 28
-1
Notes:
Fuel hoses in the engine compartment must be
secured with spring-type clamps. Screw-type
clamps or equivalent must not be used.
The Engine Control Module (ECM) has On
Board Diagnostic (OBD) capability, and is
equipped with Diagnostic Trouble Code (DTC)
memory. Before repairing or adjusting any
components or systems, first check DTC
memory. Also check all vacuum connections for
leaks ("false air").
For proper operation of electrical and electronic
components, a Battery Positive Voltage (B+)
supply of at least 11.5 volts is required.
Do not use any gasket sealers or other
automotive chemical compounds that contain
silicone. Traces of silicone drawn into the
engine pass unburned into the exhaust and can
damage the oxygen sensors.
Do not use any electrical contact sprays or
equivalent near oxygen sensor connections.
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Page 22 of 166
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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Page 23 of 166

24-18
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 -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 (001),
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:
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
for another 2 minutes.
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Page 24 of 166
24-19
- Compare display with specified values (display
fields 1-4):
Display fields
1 2 3 4
Display group 1: Engine idle speed
Display xxxx RPM
xx.x C
xx.x% xx.x %
Indicates Idle speed
(in 40 RPM steps) Engine Coolant
Temperature (ECT) Oxygen Sensor
(O2S) control, Bank
1 Oxygen Sensor
(O2S) control, Bank
2
Range 0 - 6800 RPM
-48.0 - 143.2 C
(-54 - 289 F)
-25.0 to +25.0 % -25.0 to +25.0 %
Specified
value 620 - 740 RPM
(all-wheel drive) 80.0 - 105.0 C
(176 - 221 F) -10.0 to +10.0 %
value must change by
at least 2 % -10.0 to +10.0 %
value must change by
at least 2 %
740 - 860 RPM
(front-wheel drive)
If not as specified Evaluation of
display group 1 page 24
-21
--- If not as specified:
- Check HO2S and O2S control before TWC
page 24
-22
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Page 25 of 166
24-20
If displayed values are OK (as specified):
-
Press button.
- Press buttons -0- and -6- to insert "End Output"
address word 06, and press -Q- button to
confirm input.
- 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
.
Note:
The increased idle speed for vehicles with front-
wheel drive is achieved if there is voltage (from
terminal 15er) supplied to terminal 10 of the
Engine Control Module (ECM).
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Page 26 of 166

24-21
Evaluation of display group 1 Display
Group: 1
Display
field: 1
Possible malfunction cause
Corrective action
less than
620
(all-wheel
drive)
or
less than
740
(front-wheel
drive)
Driving mode engaged
Adaptation of throttle valve control module -J338- to
engine control module cannot be conducted
Throttle valve control module malfunction- Move selector lever into "P" or "N" position
- Carry out adaptation of throttle valve control
module -J338- to ECM page 24
-150
- Check -J338- page 24
-128
less than
740
(front-wheel
drive)
B+ (15) to terminal 10 of ECM missing- Check voltage supply to terminal 10 on ECM
per wiring diagram
greater than
740
(all-wheel
drive) Adaptation of throttle valve control module -J338- to
engine control module cannot be conducted
Closed Throttle Position (CTP) switch open
Throttle valve control module malfunction- Carry out adaptation of throttle valve control
module -J338- to ECM page 24
-150
- Check -J338- page 24
-128
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Page 29 of 166
Wiring diagram
Test conditions
Engine Coolant Temperature (ECT) at least
80 C (176 F)
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