G62 AUDI A4 1999 B5 / 1.G AEB Engine Motronic MFI And Ignition System

24-2


1 -
Heated Oxygen Sensor (HO2S) -G39- with
Oxygen Sensor (O2S) heater -Z19-
2 -
Engine Coolant Temperature (ECT) sensor
-G62-
4-pin connector
3 -
Harness connector for: Heated Oxygen Sensor (HO2S) -G39- and
Oxygen Sensor (O2S) heater -Z19- (4-pin,
brown) Oxygen Sensor (O2S) behind Three Way
Catalytic Converter (TWC) -G130- with
Oxygen Sensor (O2S) heater -Z29- (4-pin,
black) Engine speed (RPM) sensor -G28- (3-pin,
gray) Knock sensor (KS) 1 -G61 (3-pin, green)Knock sensor (KS) 2 -G66- (3-pin, blue)
4 -
Electronics box (E-box) with: Motronic Engine Control Module (ECM) -
J220- Barometric Pressure (BARO) sensor -F96-
Pa
ge 2 of 135 Motronic Multi
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(MFI
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11/19/2002 htt
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play?action=Goto&t
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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
.
Pa
ge 88 of 135 Motronic Multi
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
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e=re
pair&id=AUDI.B5.FU02.24.1

- Disconnect 4-pin connector from ECT sensor -
G62-.
Pa
ge 89 of 135 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
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

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
.
Pa
ge 91 of 135 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
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

24-92


Note:
When reinstalling the fuel injectors be careful not to damage the O-rings. - Disconnect harness connector for Engine Coolant Temperature (ECT)
sensor -G62-.
-
Adjust VAG 1630 digital potentiometer to 15 k setting.- Connect to ECT sensor harness connector terminals 1 and 3, using
adapter cables from VW 1594 connector test kit.
- With the aid of a helper, briefly crank starter.
Fuel injectors must spray according to the firing order.
- Switch ignition off, and check for leaks at fuel injectors.
Fuel injectors may not drip more than 2 drops per minute.
Pa
ge 126 of 135 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
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