AUDI A6 1995 C5 / 2.G AHA Engine Multiport Fuel Injection And Ignition System Service Manual

24-31
If wiring is OK:

- Replace Motronic ECM -J220- page 01
-68
.

- Carry out adaptation of throttle valve control
module to ECM page 24
-150
.

- Check readiness code page 01
-70
. If
Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code page 01
-73
.
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24-32

Checking HO2S wiring, bank 2, sensor 1

- Disconnect 4-pin connector (black) for HO2S -
G108-.

- Connect VAG1598/22 test box to ECM harness
connector page 01
-67
.

- Check wiring for open circuit between ECM/test box and 4-pin HO2S
harness connector (to ECM).

Connector terminal 3 to ECM/test box socket 39
Connector terminal 4 to ECM/test box socket 40
Specified value: max. 1.5
- Check wiring for short circuits between terminals of 4-pin connector,
and between connector and ECM/test box.

Connector terminal 4 to ECM/test box socket 39
Specified value:
- Check wiring for short circuits to wiring harness shielding.

Connector terminal 3 to ECM/test box socket 14
Connector terminal 4 to ECM/test box socket 14
Specified value:
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24-33
If wiring is OK:

- Replace Motronic ECM -J220- page 01
-68
.

- Carry out adaptation of throttle valve control
module to ECM page 24
-150
.

- Check readiness code page 01
-70
. If
Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code page 01
-73
.
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24-34

Oxygen Sensor (O2S) heater before
TWC, checking


Notes:

Connector for Oxygen Sensor (O2S) heater -
Z19- (bank 1, sensor 1): 4-pin, black.
Connector for Oxygen Sensor (O2S) 2 heater -
Z28- (Bank 2, sensor 1): 4-pin, black.
Component locations page 24
-1 .

Required special tools and test equipment

VAG1551 or VAG1552 Scan Tool (ST) with
VAG1551/3 adapter cable
VAG1598/22 test box
Multimeter US1119 (Fluke 83 or equivalent)
VW1594 connector test kit
Wiring diagram

Test requirements
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Fuse for Oxygen Sensor (O2S) heater(s) OK
Engine Coolant Temperature (ECT) at least
80 C (176 F)
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24-35

Checking

- Connect VAG1551 or VAG1552 scan tool and
press buttons -0- and -1- to insert "Engine
Electronics" address word 01 (with engine
running at idle) page 01
-8 .
Rapid data transfer
HELP
Select function XX

Indicated on display
- Press buttons -0- and -8- to select "Read Measuring Value Block"
function 08, and press -Q- button to confirm input.
Read Measurin
g Value Block
HELP
Input displa
y group number XXX

Indicated on display
- Press buttons -0-, -4- and -0- to input display group number 40 (040),
and press -Q- button to confirm input.
Read Measuring Value Block 40 1 2 3 4

Indicated on display (1-4 = display fields)
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24-36

- Compare display and specified values (display
fields 1 and 2):

Display fields

1 2 3 4
Display group 40: Oxygen Sensor (O2S) heating (before and after TWC)
Display
xx.x
Htg.bC.ON/Htg.bC.OFF
xx.x
Htg.aC.ON/Htg.aC.OFF
Indicates Resistance of O2S heater
(before TWC)
(B1-S1 and B2-S1) O2S heater ON
or
O2S heater OFF
(before TWC)
(B1-S1 and B2-S1) Resistance of O2S heater
(after TWC)
(B1-S2 and B2-S2) O2S heater ON
or
O2S heater OFF
(after TWC)
(B1-S2 and B2-S2)
Range
0.0 - 65.0
--- --- ---
Specified value
2.4 - 9.2
Htg.bC.ON --- ---

If not as specified page 24
-37
, Continuation
--- ---
If displayed values are OK (as specified):

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

- Switch ignition off.
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24-37

Continuation

- Disconnect 4-pin connector (black) for
respective Heated Oxygen Sensor (HO2S).

If resistance is NOT OK: - Connect multimeter US1119 (Fluke 83 or equivalent) between HO2S
connector terminals 1 and 2, using VW1594 connector test kit.
- Measure resistance.

Specified value: 0.0-19.9 - Replace respective Heated Oxygen Sensor (HO2S).
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24-38
If resistance is OK:

- Switch multimeter to 20 VDC measuring
range.

If display = Htg.bC.ON:
If display switches between "Htg.bC.ON" and "Htg.bC.OFF:" - Connect multimeter between harness connector terminals 1 and 2 (to
ECM), using VW1594 connector test kit.
- Measure voltage supply and check display in display group 40, display
field 2.
Specified value: 11.0-14.5 volts Specified value: 0.0-12.0 volts (oscillating)
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11/23/2002 htt
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1