sensor AUDI A6 2000 C5 / 2.G AEB Engine Motronic MFI And Ignition System

24-66
If NOT:

- Replace Engine Coolant Temperature (ECT)
sensor -G62-.

-
Press button to advance program
sequence.
- Press buttons -0- and -6- to select "End Output"
function 06, and press -Q- button to confirm
input.

- Switch ignition off.
Evaluation of display group 1 Display group: 1


Display field: 2
Possible cause
Corrective action
approx. -46.5 C
Open circuit or short circuit in wiring to B+ - Check wiring Page 24
-66
approx. 141.0 C
Short circuit to Ground

Checking wiring

- Connect VAG 1598/22 test box to ECM harness
connector Page 01
-56
.
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- Disconnect 4-pin connector from ECT sensor -
G62-.
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24-67


- Check wiring resistance for open circuit between ECM/test box and 4-
pin ECT sensor connector.

Connector terminal 1 to ECM/test box socket 53
Connector terminal 3 to ECM/test box socket 67
Specified value: max. 1.5

- Check wiring for short circuit between ECM/test box and 4-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 3
Connector terminal 3 to vehicle Ground
Specified value:
- Check wiring between ECM and 4-pin harness connector for short
circuit to battery B+. Specified value: 0 volts

Connector terminal 1 to vehicle Ground
Connector terminal 3 to vehicle Ground
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24-68
If wiring is OK:

- Check ECT sensor resistance across terminal 1 (signal) and terminal 3
(ground).
- Check measured resistance value for appropriate temperature range
using graph below (N24-0157).

Range A: 0 to 50 C

Range B: 50 to 100 C

Examples:
If resistance is NOT OK:
At 30 C, ECT sensor resistance should be 1500-2000 At 80 C, ECT sensor resistance should be 275-375
- Replace Engine Coolant Temperature (ECT) sensor -G62-.
- Check readiness code Page 01
-59
. If Diagnostic Trouble Code
(DTC) memory has been erased, or ECM was disconnected, generate
new readiness code Page 01
-62
.
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24-69

Intake Air Temperature (IAT) sensor,
checking


Required special tools and test equipment

VAG 1551 or VAG 1552 Scan Tool (ST) with
VAG 1551/3 adapter cable
VAG 1598/22 test box
Multimeter US 1119 (Fluke 83 or equivalent)
VW 1594 connector test kit
Wiring diagram
Chilling spray (commercially available)
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24-71

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

Display fields

1 2 3 4
Display group 4: Engine basic settings
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)

--- --- --- Continuation Page 24
-72
, Evaluation of
display group 4
1) If temperature displayed deviates significantly from ambient temperature, check sensor wiring for contact resistance or
open circuit.
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24-72
Evaluation of display group 4 Display group: 4


Display field: 4
Possible cause
Corrective action
-46.5 C
Open or short circuit in wiring to B+ Page 24
-72
, check wiring
141.0 C
Short circuit to ground
approx. ambient temperature Signal intermittently interrupted
Continuation of test, page Page 24
-74
- Check IAT sensor

Wiring, checking:

- Switch ignition off.

- Connect VAG 1598/22 test box to ECM harness
connector Page 01
-56
.

- Disconnect 2-pin connector from Intake Air
Temperature (IAT) sensor -G42-.

- Check wiring for open circuit between ECM/test box and 2-pin IAT harness
connector (to ECM).

Connector terminal 1 to ECM/test box socket 54
Connector terminal 2 to ECM/test box socket 67
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24-73

- 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

Connector terminal 2 to vehicle Ground

Specified value:

- Check wiring between ECM and 2-pin harness
connector for short circuit to battery B+.


Connector terminal 1 to vehicle Ground

Connector terminal 2 to vehicle Ground

Specified value: 0 volts

- Check resistance across terminals of IAT sensor -G42-.
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If resistance is NOT OK:
Specified value: approx. 1.6-2.8 k- Replace intake air temperature sensor -G42-.
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24-74

Continuation of test
(when IAT sensor indicates approx. ambient
temperature)

- Without disconnecting harness connector,
remove IAT sensor -G42-.

- Monitor intake air temperature value in display
field 4.

- Spray sensor with commercially available
chilling spray and check temperature value in
display field 4.

Temperature value must decrease
If NOT:

- Replace intake air temperature sensor -G42-.

- Check readiness code Page 01
-59
. If
Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code Page 01
-62
.
Pa
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port Fuel In
jection
(MFI
) and i
gnition s
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11/19/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU02.24.1