AUDI A4 1999 B5 / 1.G AFC Engine Sensor For EVAP Canister Checking Workshop Manual

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Sensor for EVAP canister,
checking

Checking function

- Use VAG 1551 scan tool to select "Read
Measuring Value Block" function 08 and display
group 030 page 01
-249
.
Read measurin
g value block 30
1 2 3 4

Indicated on display
CAUTION!
Always use a second person to operate the VAG 1551 scan tool.
If display shows 0_00X
On Board Diagnostic program is not yet concluded.
If display shows 1_11X
This indicates how On Board Diagnostic recognizes a malfunction in the - Carry out test drive.
- Check value in display field 4.
Specified value: 0_11X
- Carry out test drive under conditions described in Repair Group 01,
until display shows 0_11X.
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fuel tank system.
- Check vacuum hose for leakage between EVAP canister and throttle
body page 24
-111
.
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If vacuum hose is OK:

If the specified value is not obtained: - Remove harness connector from sensor for EVAP canister.
- Switch multimeter (Fluke 83 or equivalent) to 20 volt range and connect
between harness connector terminals 1 (GND) and 3 (B+).
- Switch ignition ON.
Specified value: approx. 5 volts
- Check wiring to ECM.

- Connect VAG 1598/19 test box to ECM page 01
-255
.
- Check following wiring connections for continuity.Sensor -G172- connector terminal
number VAG 1598/19 test box socket
number
1
3 C2
C6 - If necessary, eliminate open or short in wiring.
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If wiring is OK and there is not at least 5 volts at
the sensor harness connector:

- Replace ECM page 01
-265
.

If wiring is OK: - Check wiring for continuity between harness connector and ECM.Sensor -G172- connector terminal
number VAG 1598/19 test box socket
number
2 B16 - If necessary, eliminate open or short in wiring.
- Replace sensor for EVAP canister -G172-.
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