2000 AUDI A8 ignition

24-51

Function test of Fuel Pump (FP) relay

- Remove driver-side storage compartment.

Repair Manual, Body
-Interior, Repair Group
68; Instrument Panel; Removing Driver
-Side
Storage Compartment


- Connect VAS5051 tester or VAG1551 scan tool
and select the control module for engine
electronics using "address word" 01 Page 01
-
9 .

Ignition must remain switched on for this.

- Initiate output Diagnostic Test Mode Page 01
-
56
and activate Evaporative Emission (EVAP)
canister purge regulator valve -N80-.

A - If relay does not trigger:
Fuel Pump (FP) relay (at position 4 of central electrics in driver's
footwell, left) must trigger and Fuel Pump (FP) must run.
- Check voltage supply of Fuel Pump (FP) relay Page 24
-52
.
- Checking activation of Fuel Pump (FP) relay Page 24
-52
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24-52
B - If relay triggers, but Fuel Pump (FP) does not
run:

- Check voltage supply for Fuel Pump (FP) and
components (via Fuel Pump -FP- relay) Page
24
-54
.

Check voltage supply of Fuel Pump (FP)
relay

- Remove Fuel Pump (FP) relay.

If specified value is not obtained:
Checking activation of Fuel Pump (FP) relay - Connect multimeter to terminal 17 of relay socket and Ground (GND)
for voltage measurement.

Specification: approx. battery voltage
- Replace central electrics.
- Switch ignition off.
- Connect VAG1598/31 test box at wiring harness to ECM, do not
connect ECM Page 24
-17
.
- Bridge terminals 1 and 65 at test box using wires from VAG1594A
adapter test kit.
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24-62

- Repair open circuit or short circuit if
necessary.

Note:
Ground (GND) from the ECM is present at terminal 2 of connector.
If specified value is not obtained: - Connect multimeter to terminal 2 and terminal 3 of connector for
voltage measurement.
- Operate starter briefly.

Specification: approx. battery voltage
- Check wire connections Page 24
-63
.

If specified value is not obtained: - Connect multimeter to terminal 1 and terminal 2 of connector for
voltage measurement.
- Switch ignition on.

Specification: about 5 V
- Check wire connections Page 24
-63
.
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yp
e=re
pair&id=AUDI.B5.FU05.24.1

24-64

Intake air system, checking for leaks
(unmetered air)


Special tools and equipment

Notes:
VAS5051 with VAG5051/1
orVAG1551 with VAG1551/3BEngine leak detection spray G 001 800 A1The negative pressure in the intake system sucks in the leak detection
spray with the unmetered air. Leak detection spray decreases ignition
quality and performance of the fuel mixture. This causes a reduction in
engine speed and a sharp increase of CO content. It is absolutely necessary to follow the safety precautions listed on the
can.
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24-66
If engine speed does not change:

-
Press button.Rapid data transfer
HELP
Select function XX

Indicated on display (function selection):
If engine speed decreases:
-
Press button.- Press buttons -0- and -6- to select "End output" and press -Q- button to
confirm input.
- Switch ignition off.
- Check sprayed part of intake system for leaks, and eliminate the error.
Pa
ge 78 of 78 Motronic in
jection s
ystem, servicin
g
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU05.24.1