AUDI A6 1999 C5 / 2.G AEB Engine Additional Signal

24-151

- Road test and compare indicated vehicle speed
with value in display field 3 (2nd technician
required).

Display fields

1 2 3 4
Display group 5: Engine Electronics
Display xxx RPM xx.xx ms xxx kph Idle
Part throt
Full throt
Decel
Enrich
Indicates Engine speed
(in 40 RPM
steps) Engine
load Vehicle speed Operating
condition
Range 0-6800 RPM --- --- ---
Specified
value --- --- Approx. vehicle speed ---

--- --- If no vehicle speed is displayed Page 24
-152
,
Continuation
---
If displayed value is OK:
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-
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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24-152

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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- Check readiness code Page 01
-59
. If DTC memory was erased, or
ECM disconnected, generate new readiness code Page 01
-62

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24-153

Transmission Range (TR) signal,
checking


Notes:

Through the multi-function Transmission Range
(TR) program switch -F125- at the transmission,
the Engine Control Module (ECM) recognizes
whether a drive range is selected (selector lever
in 2/3/4/R/D) or not (selector lever in P or N)
The multi-function Transmission Range (TR)
program switch -F125- at the transmission
switches to Ground through terminal 22 of the
ECM when the shift lever is in N or P.
When a drive range is selected, the switch
opens and terminal 22 now has power.

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

Test procedure

-
Connect VAG 1551 or VAG 1552 scan tool and
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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.
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24-154

Read Measurin
g Value Block
HELP
Input display group number XXX

Indicated on display
- Press buttons -0-, -5- and -6- to input display group number 56, and
press -Q- button to confirm input.
Read Measuring Value Block 56 1 2 3 4

Indicated on display (1-4 = display fields)
- Compare display with specified value in display field 4:

Display fields

1 2 3
4
Display group 56: Engine idle
Display xxxx RPM xxxx RPM x.xx g/s
xxxx
Indicates Actual engine
speed
(in 10 RPM
steps) Specified engine
speed
(in 10 RPM
steps) Control value-Idle mass air flow
(idle air control valve) Operating condition
Range 0-2550 RPM --- ---
---
Specified
value 0 RPM 0 RPM -1.11 to 1.11 g/s
0000 = Selector lever in P or N
0010 = Selector lever in 2/3/4/R/D

--- --- ---
If not as specified Page 24
-155
,
Continuation;
Explanation of display Page 24-
16

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24-155
If displayed value is OK (as specified):

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

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

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

- 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 (battery
voltage, terminal 30) and 22.


LED must come on with selector lever in P
or N

LED must then go out when selecting
2/3/4/R/D
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If the LED lights up continuously or does not light
up at all:

- Check wiring for open circuit, short circuit to Ground or short circuit to
B+ between ECM/test box socket 22 and multi-function Transmission
Range (TR) program switch -F125-.
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24-156
If the wiring is OK:

- Check multi-function Transmission Range (TR)
program switch -F125-.

Repair Manual, 5 Spd. Automatic
Transmission 01V, Repair Group 01


- Check readiness code Page 01
-59
. If
Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code Page 01
-62
.
Explanation of 4-digit display
Explanation when display field is = 0
x
x
x
x
(Display group 56)
0 A/C compressor off (0 = A/C compressor off / 1 = A/C compressor on)
0 Selector lever in P or N (0 = selector lever in P or N /1 = selector lever in 2/3/4/R/D)
0 Always "0"
0 Always "0"
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