2000 AUDI A4 battery

01-165
Display group 001 Display shows
Display/specified value
Designation
Basic setting 1
1 2 3 4 85-110 C
1 = Coolant temperature
1.450-1.580 V2) 2 = Mass Air Flow (MAF) sensor1) output voltage
0 - 255 3 = Altitude display
12.000 - 14.000 V 4 = Engine Control Module (ECM) voltage supply battery voltage
1) specified value minus 0.01 V per 500 m above sea level. 2) Mass Air Flow (MAF) sensor output voltage tolerance range can only be evaluated during basic setting at idle.
Note on display field 3:
The altitude display is a calculated value inside the engine control module that is calculated by a comparison of the intake air
mass and the throttle angle.
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and starts to go up again
4 Greater than
14.000 V
or
Less than
12.000 V
Generator faulty
Overvoltage because of starting aid
Poor ground connection to ECM -J192-
Discharged battery
Current draw with ignition off - Check voltage
- Check battery charging status
- Check voltage supply of Engine Control
Module (ECM) Repair Group 28
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01-201
Display group 018 Display
shows Specified display
value Designation
Basic setting
18
1 2 3 4 __ % 1 = Internal duty cycle (triggering) - Idle Air Control (IAC) valve -N71-
_.___ A 2 = Idle Air Control (IAC) valve -N71- current
-40 to +60% 3 = Power control from Idle Air Control (IAC) valve -N71-
12,000 - 14,000 V 4 = Engine Control Module (ECM) -J192- voltage supply (battery voltage) display
group 001, display field 1 Note on display field 1:
The internal calculation value in the engine control module for the duty cycle is displayed without power and voltage
correction.
Note on display field 2:
The actual power draw by the Idle Air Control (IAC) valve -N71- is displayed.
Note on display field 3:

Positive values indicate increase in the duty cycle, in order to reach the specified current.
Negative values indicate a decrease in the actual duty cycle to reach the specified current.
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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."
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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
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01-231
Display group 040 (Heating current of oxygen sensors in front of and behind three way catalytic converter) Display
shows Display specified value
Designation/diagnosis
Basic setting
40
1 2 3 4 At cold start, greater than 3 A after approx. 40 sec: 0.7 -
1.0 A 1 = Heating current, bank 1, heated oxygen
sensor 1
2 = Heating current, bank 2, heated oxygen
sensor 1
At cold start, greater than 3 A after approx. 80 sec: 1.2 -
1.4 A 3 = Heating current, bank 1, heated oxygen
sensor 2
4 = Heating current, bank 2, heated oxygen
sensor 2 Notes:

The current values specified apply only at when battery positive voltage (B+) is 12-14 volts display group 001, display
field 4. The heating of the heated oxygen sensors in front of the three way catalytic converter is switched on with the fuel pump
relay, i.e. immediately at engine start.
The heating of the heated oxygen sensors behind the three way catalytic converter is not switched on immediately at
engine start, but only when the calculated exhaust gas temperature in the three way catalytic converter exceeds 308 C
(586 F) display group 044, display field 2. In order to reach an exhaust gas temperature of 308 C (586 F) in the three
way catalytic converter after a cold start, the car must be driven about 20 sec. with an increased engine speed of 2500
RPM.
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01-256

Readiness code, reading and generating


Note:
OBD II legal regulations require a display
(readiness code) that shows inspection
readiness for the annual exhaust emissions test.
The readiness code shows that every component
and/or system that affects exhaust emissions,
which can lead to the MIL switching on, has been
operated at least once with positive results.

Note:
The readiness code is reset and/or erased every
time:

DTC memory is erased (either with display
group 01 function 05 or display group 33 mode
4)
ECM harness connector is disconnected from
ECM -J192- (e.g. connecting test box VAG
1598/19, replacing ECM, etc.)
Battery is disconnected
Pa
ge 355 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1