check engine AUDI A4 2000 B5 / 1.G AHA Engine Throttle Valve Control Module Checking Workshop Manual

24-129

Function

Idle speed stabilization is integrated in the
throttle valve control module -J338-. In the
housing opposite the throttle valve are Throttle
Position (TP) sensor -G69-, Closed Throttle
Position (CTP) switch -F60-, throttle drive -G186-
and angle sensor -1- for throttle drive -G187-.

The housing should not be opened.
The individual components cannot be replaced or
mechanically adjusted. All adjustments are
accomplished by the VAG1551 Scan Tool (ST)
using the "Basic Setting" function 04.
If the complete throttle valve control module is
without power (i.e. disconnected), the throttle
valve assumes a mechanical closed throttle
position that results in an increased idle speed of
1200-1300 RPM (with engine at operating
temperature).
If only the Throttle Position (TP) actuator -V60- is
without power, the throttle valve also assumes a
mechanical closed throttle position (limp-home
position), but because the signal from the CTP
switch -F60- can still be recognized, a nearly
"normal" idle speed of approx. 900 RPM is
maintained with a corresponding reduction of the
ignition timing advance.
If the Engine Control Module (ECM) recognizes a
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If wiring is OK: - Check wiring for short circuit between ECM/test box and 8-pin harness
connector.

Connector terminal 7 to ECM/test box socket 69
Connector terminal 7 to ECM/test box socket 62
Connector terminal 4 to ECM/test box socket 67
Specified value:
- Reconnect throttle valve control module harness connector.
- Replace Motronic Engine Control Module (ECM) -J220- page 01
-
68
.
- Carry out adaptation of throttle valve control module to ECM page
24
-150
.
- 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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24-132

Closed Throttle Position (CTP) switch,
checking


Note:
The Closed Throttle Position (CTP) switch -F60-
is inside the throttle valve control module -J338-.

Test conditions

Throttle valve in closed throttle position; if
necessary adjust accelerator pedal cable

Repair Manual, Fuel Supply System, Repair
Group 20


Cruise control adjustment OK
Power supply for throttle valve control
module OK; checking page 24
-130


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 .
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24-133

- Press buttons -0-, -0- and -5- to input display
group number 5 (005), and press -Q- button to
confirm input. Read Measuring Value Block 5 1 2 3 4

Indicated on display (1-4 = display fields)
- Check Closed Throttle Position (CTP) switch (display field 4):

Display fields

1 2 3 4
Display group 5: Engine electronics
Display xxx RPM xx.xx ms xxx km/h Idle
Part throt
Full throt
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) 1.00 - 2.50 ms 0 km/h Throttle closed: "Idle"
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24-136

Throttle drive and angle sensor for
throttle drive, checking


Note:
Throttle drive -G186- and angle sensor -1- for
throttle drive -G187- are located in the throttle
valve control module -J338-.

Test conditions

Throttle valve in closed throttle position; if
necessary adjust accelerator pedal cable

Repair Manual, Fuel Supply System, Repair
Group 20


Cruise control adjustment OK
Power supply for throttle valve control
module OK; checking page 24
-130


Engine coolant temperature at least 80 C
(176 F)

Automatic transmission selector lever in "P"
or "N"
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24-137

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.
Read Measurin
g Value Block
HELP
Input displa
y group number XXX

Indicated on display
- Press buttons -0-, -5- and -5- to input display group number 55 (055),
and press -Q- button to confirm input.
Read Measuring Value Block 55 1 2 3 4

Indicated on display (1-4 = display fields)
- Compare display with specified values for idle air control (display fields
1-4):
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24-138


Display fields

1 2 3 4
Display group 55: Idle control
Display xxx RPM x.xx g/s x.xx g/s xxxx
Indicates Engine speed RPM
(in steps of 10 RPM) Regulating value-idle mass air
flow (idle air control) Learning value-idle
mass air flow Operating
conditions
Range 0 - 2550 RPM -2.78 to +2.85 g/s -1.67 to +3.34 g/s ---
Specified
value 620 - 740 RPM
(all-wheel drive)
or
740 - 860 RPM
(front-wheel drive) -1.39 to +1.39 g/s -1.39 to +1.39 g/s 0000
(all-wheel drive)
and/or
0100
(front-wheel
drive)

If engine speed is NOT OK page
24
-141
, Continuation
If display is NOT OK page 24
-139
, Evaluation of
display group 55
Explanation
page 24
-140


If displayed values are OK:

-
Press button.
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24-139
Evaluation of display group 55 Display group:
55


Display fields:
2 3
Possible malfunction cause
Corrective action
above 1.39 g/s

Increased load because of switched-
on consumers - Switch off electrical consumers

Throttle valve mechanism sticking
Air passage in area of throttle valve
contaminated - Visually check, repair if necessary
below -1.39 g/s
Intake air leak (false air) behind
throttle valve - Check intake air system for leaks (false air) page 24
-126
- Check exhaust system Repair Manual, 2.8 Liter V6 5V
General, Engine, Repair Group 26
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24-140
Explanation of 4-digit display
Explanation when display field is = 0
x
x
x
x
Display group 55
0 A/C compressor off (0 = A/C compressor off; 1 = A/C compressor on)
0 Shift lever in P or N (0 = Shift lever in P or N; 1 = Shift lever in 2/3/4/R/D)
0 Idle air control boost (0 = no idle air control boost, for all-wheel drive vehicles; 1 = idle air control boost, for
front-wheel drive vehicles)
0 always "0"
Note:
The increased idle speed (raised rpm) on vehicles with front-wheel drive is attained if there is power supplied (B+, 15er) to
terminal 10 of the engine control module.
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24-143

Throttle Position (TP) sensor, checking


Note:
The Throttle Position (TP) sensor -G69- is
located inside the throttle valve control module -
J338-.

Test conditions

Throttle valve in closed throttle position; if
necessary adjust accelerator pedal cable

Repair Manual, Fuel Supply System, Repair
Group 20


Cruise control adjustment OK
Power supply for throttle valve control
module OK; checking page 24
-130


Checking

- Connect VAG1551 or VAG1552 scan tool and
press buttons -0- and -1- to insert "Engine
Electronics" address word 01 (with ignition
switched; engine not running) page 01
-8 .
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