AUDI A6 1997 C5 / 2.G AEB Engine Additional Signal

24-157

Timing control during shifting, checking


Notes:

When shifting the automatic transmission, this
signal from the Transmission Control Module
(TCM) retards the ignition timing briefly,
depending on vehicle speed and engine RPM
(reduction of torque), to reduce shift pressure.
Because of the very brief signal to reduce
torque, the signal is not always recognized by
the VAG 1551 scan tool, and therefore is not
always indicated.

Required special tools and test equipment
VAG 1551 or VAG 1552 Scan Tool (ST) with
VAG 1551/3 adapter cable
VAG 1598/22 test box
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24-158

Test procedure

- 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 1, 2 and 2- to input display group number 122, and press
-Q- button to confirm input.
Read Measuring Value Block 122 1 2 3 4

Indicated on display (1-4 = display fields)
WARNING!
A second technician is required to operate the VAG 1551 scan tool
during the road test. - Road test.
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24-159

- Compare display with specified value in display
field 4:

Display fields

1 2 3 4
Display group 122: Engine torque reduction during shifting
Display xxxx RPM xxx Nm xxx Nm TCS active
Motor enga
Indicates Engine speed
(in 40 RPM
steps) Required engine
torque
(Specified torque) Actual engine
torque
(Actual torque) Timing angle retard active or not active
Range 0-6800 RPM -100 to 410 Nm -100 to 310 Nm ---
Specified
value --- --- --- When shifting, "Motor enga" must be
displayed briefly

--- --- --- If not as specified Page 24
-160

If display is OK (as specified):

-
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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- Switch ignition off.
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Continuation

Note:
The wiring to the Transmission Control Module is
monitored by On Board Diagnostic and stores
the Diagnostic Trouble Code 00545 if there is a
malfunction.
If displayed value is NOT OK (not as specified),
or if DTC 00545 is stored in DTC memory:

- Connect VAG 1598/22 test box to ECM harness
connector Page 01
-56
.

Electrical Wiring Diagrams, Troubleshooting & Component Locations - Check wiring for short circuit or open circuit between ECM harness
connector terminal 23 and to Transmission Control Module (TCM),
according to wiring diagram
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24-161

Rough road signal from ABS/EDL
control module, checking


Notes:

When the ABS/EDL control module senses a
wheel spinning, it produces the rough road
signal. When the ECM recognizes the rough
road signal, the misfire recognition is switched
off.
Check the rough road signal only when the
trouble code 18014 "Rough Road Spec Engine
Torque ABS-ECU Electrical Malfunction" is
stored. The "Misfire" malfunction is in this case
a subsequent malfunction that can be
disregarded.
The wiring and the rough road signal are
monitored by the ECM.
Emissions testing on a front-wheel drive vehicle
with ABS/EDL, during which only the front
wheels turn while the rear wheels are
stationary, can result in the DTC 18014 being
stored in DTC memory. Therefore, the fuse for
the ABS/EDL control module must be removed.
After the test, check DTC memory for the
ABS/EDL control module and the ECM. Then
erase DTC memory.
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Required special tools and test equipment

VAG 1551 or VAG 1552 Scan Tool (ST) with
VAG 1551/3 adapter cable
VAG 1598/22 test box
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24-162

Test requirements

ECM coding OK Page 01
-13


Test sequence

- Switch ignition off.

- Connect VAG 1598/22 test box to ECM harness
connector Page 01
-56
.

- Check signal wiring for short circuit or open
circuit between ECM/test box and ABS control
module, according to wiring diagram.
If the wiring is OK:

- Replace ABS control module.
If the malfunction occurs again after the ABS
control module has been replaced:

- Replace Motronic ECM -J220- Page 01
-57
.

- Carry out adaptation of throttle valve control
module to ECM Page 24
-119
.

-
Check readiness code Page 01
-59
. If
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Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code Page 01
-62
.
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