1999 AUDI A4 heater

01-37

DTC
Description of malfunction
Corrective action
SAE
VAG


P1136 17544 Long Term Fuel Trim Add. Fuel,
Bank1
System too Lean
2) - Carry out road test (fuel in engine oil)
P1137 17545 Long Term Fuel Trim Add. Fuel,
Bank1
System too Rich
2) - Check fuel pressure Page 24
-33
P1138 17546 Long Term Fuel Trim Add. Fuel,
Bank2
System too Lean
2) - Check Mass Air Flow (MAF) Sensor Page 24
-59
P1139 17547 Long Term Fuel Trim Add. Fuel,
Bank2
System too Rich
2) - Check oxygen sensor before catalytic converter Page 24
-81
- Check oxygen sensor behind catalytic converter Page 24
-
100

- Check EVAP canister valve 1 Page 24
-134
P1140 17548 Bank2-Sensor2
Internal Resistance too High
2) - Check oxygen sensor heater Page 24
-114
.
- Check oxygen sensor signal wire and activation Page 24
-
122

2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is
recognized after the engine has been restarted. Significance of MIL Page 01
-3 .
Pa
ge 45 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

01-103

X
X
X
X
X
X
X
X
Notes for display group 086 display field 1 (Ready-Bits)

1 = Three Way Catalytic Converter (TWC) (diagnostic of catalytic converter)

Display 0 = ready
Display 1 = not ready (Readiness code generating Page 01
-105
)

2 = TWC Catalytic Converter (not available/always "0")

3 = EVAP system (0 = ready)

Display 0 = ready
Display 1 = not ready (Readiness code generating Page 01
-105
)

4 = Secondary Air Injection (AIR) System

Display 0 = ready
Display 1 = not ready (Readiness code generating Page 01
-105
)

5 = Climate Control (diagnosis not applicable/always "0")

6 = Oxygen sensors

Display 0 = ready
Display 1 = not ready (Readiness code generating Page 01
-105
)

7 = Oxygen sensor (O2S) heater

Display 0 = ready
Pa
ge 124 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

01-117
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