heater AUDI A4 1999 B5 / 1.G APB Engine Motronic Syst

01-117
If specified value in display "System OK" is
reached:

- Press -C- button.

Work step 7: Diagnosis of oxygen sensor
heater System in Basic Setting
Q
Input displa
y group number XXX

When indicated on display
- Press buttons -0-, -4- and -1- to select display group number 041 and
confirm with -Q- button.
System in Basic Setting 41
1
2
3
4

When indicated on display
Note:
Increasing engine speed accelerates the obtaining of specified values. - Check specified value in display field 1 and 3:
Pa
ge 141 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-118


Display fields

1 2 3 4
Display group 041: Oxygen sensor heater, bank 1
Display
xxx kOhm
Heater before before CAT
ON xxx kOhm
Heater before behind CAT
ON
Indicated
Bank 1, Sensor 1
Condition of heater
Bank 1, Sensor 2
Condition of heater
Work range
Heater b. CAT ON
Heater b. TWC OFF
Heater a. CAT ON
Heater a. CAT OFF
Specified
value 0 - 0.5 kOhm
Heater b. CAT ON/OFF
0 - 0.9 kOhm
Heater a. CAT ON/OFF Important note for display fields 1,2,3 and 4:

Display fields 1 and 3 will not indicate any value if the operating temperature of the oxygen sensors is not reached, that
means both fields are empty. (Increase Engine Speed to reach specified value).
After the operating temperature is reached, the display fields 1 and 3 must display a value of less than 0.5K Ohm
Only proceed with test after value of less than 0.5K Ohm is displayed with in display fields 1 and 3.
The Engine Control Module (ECM) cycles at certain operating conditions the oxygen sensor heating, that means, the
heater is certain operating conditions ON or OFF. It is therefore possible that the specification in display field 2 and 4
appears periodically as "Heater b. CAT OFF" or "Heater a. CAT OFF"
Pa
ge 142 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-119


Display fields

1 2 3 4
Display group 042: Oxygen sensor heater, bank 1
Display
xxx kOhm
Heater before before CAT
ON xxx kOhm
Heater before behind CAT
ON
Indicated
Bank 1, Sensor 1
Condition of heater
Bank 1, Sensor 2
Condition of heater
Work range
Heater b. CAT ON
Heater b. TWC OFF
Heater a. CAT ON
Heater a. CAT OFF
Specified
value 0 - 0.5 kOhm
Heater b. CAT ON/OFF
0 - 0.9 kOhm
Heater a. CAT ON/OFF
Note
Observe note
below
Observe note
below Important note for display fields 1,2,3 and 4:

Display fields 1 and 3 will not indicate any value if the operating temperature of the oxygen sensors is not reached, that
means both fields are empty. (Increase Engine Speed to reach specified value).
After the operating temperature is reached, the display fields 1 and 3 must display a value of less than 0.5K Ohm
Only proceed with test after value of less than 0.5K Ohm is displayed with in display fields 1 and 3.
Pa
ge 144 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

The Engine Control Module (ECM) cycles at certain operating conditions the oxygen sensor heating, that means, the
heater is certain operating conditions ON or OFF. It is therefore possible that the specification in display field 2 and 4
appears periodically as "Heater b. CAT OFF" or "Heater a. CAT OFF"

- Press -C- button.
Pa
ge 145 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1