1998 AUDI A4 ECO mode

01-176

Display
field Display on VAG 1551
scan tool Malfunction cause
Malfunction repair
4 Not 001 10
Closed Throttle Position (CTP) switch -F60 activated or faulty A/C compressor switched on Rear window heating switched on Driving mode selected (automatic
transmission) - Check and adjust -F60- page 24
-
73

- Switch A/C off
- Check A/C compressor shut-off
page 24
-90

- Move selector lever to P or N
Note:
Display field 4 (shift inputs) can be used to recognize whether the components described below are recognized by the Engine
Control Module (ECM) as switched on or off. Display group 023 gives an exact description of the shift inputs. 0
0
1

1
0
Meaning of 5-digit shift inputs

1 = Shifting Signal (0 = not active / 1 = active)

2 = Gear recognition signal (always "1" except that display = "0" for automatic transmission vehicles with
gear engaged)

3 = -----------

4 = Mechanical Closed Throttle Position (CTP) switch (1 = closed / 0 = open)

5 = A/C compressor OFF/ON (0 = off, 1 = on)

6 = Rear window heater signal (always "0" except for vehicles without A/C and with rear window heater
on)
Pa
ge 247 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-206
Note on display field 2: X
X
Meaning of 2-digit display:

1 = Shifting signal (ignition angle retard):
Value "0" = Ignition angle retarding not active
Value "1" = Ignition angle retarding active
Notes:

Because of the brief signal, the shift is not always displayed.
On vehicles without automatic transmission, "0" is always displayed.
Check shift signal page 24
-101
.

2 = Gear recognition signal:
Value "0" = Selector lever in R, D, 4, 3, or 2 (driving mode engaged)
Value "1" = Selector lever in P or N
Notes:

On vehicles without automatic transmission, "0" is always displayed.
Check gear recognition signal page 24
-99
.
Pa
ge 291 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-211
Display group 029 (Diagnosis status)
Notes:
OBD II regulations require a display ("Readiness Code") that indicates readiness for inspection (annual exhaust emissions
test). The readiness code display (display field 1) shows that every component and/or system that affects the exhaust, which
can lead to switching on the MIL, has been operated at least once with positive result.
The readiness code is reset and/or erased:

Every time the DTC memory is erased (both with address word 01 function 05 and with address 33 mode 4).
When the battery is disconnected.
When the engine control module is disconnected (e.g. connecting test box VAG 1598/19, replacing ECM, etc.).
To generate the readiness code, take a "mixed city and highway" drive (short test). A "mixed city and highway" drive is
understood to be approx. 1-1/2 to 5 minutes at 80-100 km/h (50-63 mph) with manual transmission in 4th or 5th gear, or
automatic transmission selector lever in "D" position, preferably in 4th gear.
The "Trip Status" display (display field 2) shows which components and/or systems have been checked since the start of the
trip. After successful diagnosis, the current display value is set to "1" whether the diagnosis was recognized as OK or not OK.
The trip-status display is reset to "0" at each start since the components and/or systems are checked at each new start. A
"trip" is understood to be a drive of approx. 1-1/2 to 5 minutes at 80-100 km/h (50-63 mph) with manual transmission in 4th or
5th gear, or automatic transmission selector lever in "D" position, preferably in 4th gear, with preceding cold start.
The readiness code display (display field 1) shows whether the components and/or systems checked in display field 2 were
recognized as OK or not OK by the engine control module.
If the diagnosis is recognized as OK, the current display value is set to "0."
Pa
ge 299 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-213
Notes on display field 1:

All readiness code values are set to "1" by disconnecting the ECM harness connector and/or disconnecting the battery,
and every time DTC memory is erased (both with address word 01 function 05 and with address word 33 mode 4).
To regenerate the readiness code, take a drive of approx. 1-1/2 to 5 minutes at 80-100 km/h (50-63 mph) with manual
transmission in 4th or 5th gear, or automatic transmission selector lever in "D" position, preferably in 4th gear ("mixed city
and highway" trip).
Value "0" = Diagnosis carried out
Value "1" = Diagnosis not OK and/or diagnosis not carried out yet
X
X
X

X
X

X
Meaning of the 6-digit "readiness codes"

1 = Three way catalytic converter diagnosis (Banks 1 and 2)

2 = ----

3 = Evaporative Emissions (EVAP) throughput diagnosis

4 = Secondary air system throughput and leak diagnosis (Always "0" for vehicles without
secondary air injection system)

5 = ----

6 = Heated oxygen sensor diagnosis (flank rise and/or flank fall time of the voltage signal of
heated oxygen sensors in front of three way catalytic converters

7 = Oxygen sensor heating diagnosis (all four O2S heaters)

8 = Exhaust Gas Recirculation (EGR) throughput diagnosis
Pa
ge 303 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-262

Step 3: Road test
In order to set the readiness code, a "mixed city
and highway" drive is required. The necessary
driving conditions for the test drive ar listed in the
following chart:

Speed Between 50 and 62 mph
RPM 1800 - 2700 RPM
Manual: 5th gear
Automatic: Drive mode "4"
Drive
Profile After attaining the specified speed (50-
62 mph) implement a short
deceleration phase (approx. 5-8
seconds), then drive if possible at
constant specified speed and RPM
range
Drive
Time Approx. 1-1/2 to 5 minutes (as long as
necessary)
Pa
ge 361 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1