heating AUDI A4 1997 B5 / 1.G AFC Engine On Board Diagnostic Multiport Fuel Injection Owner's Manual

(for diagnostic conditions display groups 007 and 008)

6 = Heated oxygen sensor diagnosis (flank rise and/or flank fall time of the voltage signal on
the heated oxygen sensor in front of three way catalytic converter; for diagnostic conditions
display group 042)
7 = Oxygen sensor heating diagnosis (all four O2S heaters)

8 = Exhaust Gas Recirculation (EGR) system throughput diagnosis
(for diagnostic conditions display group 017)
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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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01-232
Display group 041 (Voltage signal of oxygen sensors in front of and behind three way catalytic converter) Display
shows Display specified
value Designation/diagnosis
Basic setting
41
1 2 3 4 _.___ V 1 = Voltage signal, bank 1, heated oxygen sensor 1 display group 010, display
field 3 _.___ V 2 = Voltage signal, bank 2, heated oxygen sensor 1 display group 010, display
field 4 _.___ V 3 = Voltage signal, bank 1, heated oxygen sensor 2
_.___ V 4 = Voltage signal, bank 2, heated oxygen sensor 2 Notes on display field 3 and 4:

The voltage signals of bank 1 heated oxygen sensor 2 and/or bank 2 heated oxygen sensor 2 should not be evaluated
until at least 50 sec. after the oxygen sensor heating is switched on display group 040. With cold engine and ignition on, a voltage signal of 0.400 volts is displayed in all four display fields. With very hot engine
and ignition on, a signal of 0.000 volts is displayed in display field 3 and 4.
The voltage signal of the heated oxygen sensors behind the three way catalytic converter must lie between about 0.5 volts
and 0.6 volts with a three way catalytic converter with sufficient effect (conversion). During deceleration fuel shut off, the
voltage signal must be less than 0.1 volts constantly. During operation with wide open throttle enrichment, the voltage
signal must be greater than 0.6 volts.
If there is wide open throttle (signal voltage during wide open throttle enrichment greater than 0.6 volts) with a new three
way catalytic converter, distance driven less than 5,000 km (3,000 mi.) after a preceding deceleration fuel shut off (signal
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01-236

X
X
X
X
X
X
X
X
Meaning of 8-digit "Diagnosis condition 2"

1 = Constant drive

2 = Oxygen sensor heating, bank 1 OK ( display group 040)
3 = Oxygen sensor heating, bank 2 OK ( display group 040)
4 = Vehicle speed: 80 - 100 km/h (50 to 63 mph) ( display group 003)
5 = Value does not drop below or exceed oxygen sensor control limit for bank 2 ( display
group 008)
6 = Value does not drop below or exceed oxygen sensor control limit for bank 1 ( display
group 007)

7 = Calculated exhaust gas temperature in front of three way catalytic converter: 400 - 640 C
(752 - 1184 F)
8 = Throttle angle constant ( display group 003) Re: 5 and 6: With a lot of fuel vapor on the EVAP system diagnosis, use function 04 to carry out "Basic Setting" (EVAP
system automatically shut off during function 04).
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01-241
Notes on display field 3 and 4:
Value "0" = Diagnosis condition not fulfilled
Value "1" = Diagnosis condition fulfilled X
X
X
X
X
X
X
X
Meaning of 8-digit display "Diagnosis condition 1"

1 = Coolant temperature: 70 - 110 C ( display group 001)
2 = Oxygen sensor heating (all four O2S heaters; display group 040)
3 = Momentary constant drive

4 = No fuel enrichment (during diagnosis no enrichment can occur)

5 = Long-term constant drive

6 = Closed throttle position switch open ( display group 002)
7 = Oxygen sensor control, bank 2 active ( display group 008)
8 = Oxygen sensor control, bank 1 active ( display group 007)
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01-264
If, during regeneration of the readiness code, the
trip status display is set to "1" but the
corresponding readiness code display is not set
to "0" the diagnosis was carried out but not
recognized as OK by the ECM.
In this case, DTC memory should be checked for
malfunctions and/or to carry out a selective
diagnosis:

- For three way catalytic convertor diagnosis
(bank 1 and bank 2), also check display groups
035, 036 and 044.

- For EVAP system leak diagnosis, also check
display group 030.

- For heated oxygen sensor diagnosis, also check
display groups 032, 033, 034, 041, 042 and 043.

- For oxygen sensor heating diagnosis, also
check display group 040.

- For Exhaust Gas Recirculation (EGR)
throughput diagnosis, also check display group
017.
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