1998 AUDI A4 ignition

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

- Switch off ignition.
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Continuation
If no speed was indicated:

Notes:
If the LED does not blink:
Electrical Wiring Diagrams, Troubleshooting & Component Locations
If the wiring is OK and the LED does not blink:
Repair Manual, Electrical Equipment, Repair Group 90
- Connect VAG 1598/22 test box to ECM harness connector Page 01
-
56
.
- Connect VAG 1527B LED voltage tester between ECM/test box
sockets 3 (B+) and 20 (signal).
- Lift vehicle at left front until wheel is free.
- Switch ignition on and rotate left-front wheel by hand.
LED must blink (very brief blink)
The right-front wheel must not rotate; block it if necessary.For LEDs with little voltage consumption, the LED lights up at half
strength when the ignition is switched on.
- Check wiring from ECM connector, terminal 20 to instrument cluster for
open circuit or short circuit
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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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- Switch ignition off.
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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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