1999 AUDI A4 battery

24-84

- Compare displayed value with specified value
for intake air temperature (display field 4):

Display fields

1 2 3 4
Display group 4: General engine data
Display xxx RPM xx.xxx V
xxx.x C
xxx.x C
Indicates Engine speed
(in 40 RPM
steps) Battery Positive
Voltage (B+) Engine coolant
temperature Intake air temperature
Range 0 - 6800 RPM 0.000 - 16.500 V -46.5 to 141.0 -46.5 to 141.0
Specified
value 0 RPM 10.000 - 14.500 V --- approx. ambient temperature 1), 2)

--- --- --- Continuation page 24
-85
, Evaluation of
display group 4
1) After a long standing period (approx. 12 hours). 2) If indicated temperature deviates significantly from the ambient temperature, check IAT sensor wiring for resistance or open
circuits.
Pa
ge 108 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1

24-86


If wiring is OK: - Check wiring for short circuit between ECM/test box and 2-pin harness
connector according to wiring diagram.

Connector terminal 1 to vehicle Ground
Connector terminal 1 to ECM/test box socket 67
Connector terminal 1 to terminal 2
Specified value:
- Check wiring between ECM and 2-pin harness connector for short
circuit to battery B+.
Specified value: 0 volts

If resistance is NOT OK: - Check resistance across terminals of IAT sensor -G42-.

Specified value at approx. 20 C (68 F): approx. 1.5-3.5 k- Replace intake air temperature sensor -G42-.
Pa
ge 111 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1

24-91

- Check battery positive voltage (B+) in display
field 2.

Display fields

1 2 3 4
Display group 4: General engine data
Display xxx RPM xx.xxx V
xxx.x C
xxx.x C
Indicates Engine speed
(in 40 RPM
steps) Battery Positive Voltage (B+)
Terminal 15 Engine coolant
temperature Intake air
temperature
Range 0 - 6800 RPM 0.000 - 16.500 V -46.5 to 141.0 -46.5 to 141.0
Specified
value 0 RPM 10.000 - 14.500 V --- ---

--- If not as specified page 24
-92
, Evaluation
of display group 4
--- ---
If displayed value is OK (as specified):

-
Press button.
- Press buttons -0- and -6- to select "End Output"
function 06, and press -Q- button to confirm
input.
Pa
ge 117 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1

24-92
Evaluation of display group 4 Display group: 4


Display field: 2
Possible malfunction
cause
Corrective action
If "Control module does not answer" is
displayed
Fuse for ECM faulty- Replace fuse
Open circuit in wiring- Check voltage supply at terminal 15 page
24
-94

Displayed value changes between 10.0 -
14.5 V
Intermittent connection- Check voltage supply at terminal 15 page
24
-94

- Check voltage supply at terminal 30 page 24
-93

0.0 - 10.0 V
Battery discharged/faulty Voltage regulator faulty- Check battery
- Check generator
- Check voltage regulator
14.5 - 16.5 V Generator faultyVoltage regulator faulty- Check generator
- Check voltage regulator
Pa
ge 118 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1

24-99

Checking fuel pump relay voltage supply and
actuation

- Remove fuel pump relay -J17- from relay panel
position 6.

Checking fuel pump relay voltage supply

- Switch ignition on.

If voltage is NOT OK: - Connect multimeter US1119 (Fluke 83 or similar) and check for voltage
at relay socket:

Terminals 28 (B+) and 34
Terminals 32 (B+) and 34
Specified values: approx. Battery Positive Voltage (B+)
- Repair wiring according to applicable wiring diagram.
Pa
ge 127 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1