relay AUDI A6 1998 C5 / 2.G ATQ Engine Motronic Injection System Servicing Workshop Manual

24-8


10 -
E-box in plenum chamber
Motronic Engine Control Module (ECM) -
J220- Secondary Air Injection (AIR) Pump Relay -
J299- Fig. 10
, page Page 24
-12

11 -
Valve -2- for camshaft adjustment -N208-
12 -
Camshaft Position (CMP) sensor 2 -G163-
Bank 1
13 -
Heated Oxygen Sensor (HO2S) -G39-
before catalytic converter with Oxygen
Sensor (O2S) Heater -Z19- Bank 1, sensor 1
14 -
Ground connection on the engine bracket, right side
15 -
Mass Air Flow (MAF) sensor -G70- Checking Page 24
-56
16 -
Evaporative Emission (EVAP) canister
purge regulator valve -N80-
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24-12


Note:
In order to assure sufficiently secure fitting, switches must not be installed
more than once.
Adjusting switch:
Repair Manual, Brake System, ABS, ABS/EDL, Repair Group 46
Fig. 9 Component location Brake Light Switch -F- and Brake
Vacuum Vent Valve Switch For Cruise Control/Diesel Fuel
Injection, Clutch Vacuum Vent Valve Switch -F36-
1 - Clip
2 - Brake Light Switch -F-, Brake Vacuum Vent Valve Switch For Cruise
Control/Diesel Fuel Injection -F47-
3 - Clutch vacuum vent valve switch -F36-

Secondary Air Injection (AIR) Pump Relay -J299- (arrow) in 3-pin relay
carrier in E-box, plenum chamber. Fig. 10 Component location for Secondary Air Injection (AIR)
Pump Relay -J299-
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24-13


Fuel Pump (FP) Relay -J17- is located at position 4 of central electrics in
driver's footwell, left. Fig. 11 Component locations Fuel Pump (FP) Relay -J17-

Data Link Connector (DLC) in knee bolster on driver's side. Fig. 12 Component location of Data Link Connector (DLC)
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24-46

Test requirement:

Fuel pressure OK, checking Page 24
-30
.

Test sequence

- Remove fuel distributor including fuel injectors
from intake manifold Page 24
-43
. Fuel lines
remain connected.

- 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
adapter cables from VAG1594A connector test
kit (this step supplies Ground -GND- to one side
of relay coil for Fuel Pump -FP- relay).

Note:
Fuel Pump (FP) relay is supplied with B+ via the
central electric (terminal 30). Fuel Pump (FP)
relay receives minus via the cable bridge in test
box. The Fuel Pump (FP) is now running
constantly.
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24-49


Fuel Pump (FP) relay -J17- and activation,
checking

Special Tools and Equipment

VAG1526A
VAG1594A
VAG1598/31
VAS5051 with VAG5051/1
- or
VAG1551 with VAG1551/3B
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24-50
Voltage is supplied to the Fuel Pump (FP) and
several components of the injection system via
the Fuel Pump (FP) relay -J17-.
Engine must be turning for Fuel Pump (FP) relay
-J17- to close. This means that the relay does
not receive Ground (GND) (via ECM) until the
ECM recognizes RPM signals.

Note:

Fuel Pump (FP) relay is located at position 4 of central electrics in driver's
footwell, left.
Test requirement:
Battery voltage at least 12.7 V
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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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24-53


If relay triggers now, but didn't during output DTM:
If relay does not trigger:
Fuel Pump (FP) relay (at position 4 of central electrics in driver's
footwell, left) must trigger.
- Replace Engine Control Module (ECM) Page 24
-21
.
- Remove cable bridge.
- Remove Fuel Pump (FP) relay.

If specified value is not obtained:
Electrical Wiring Diagrams, Troubleshooting & Component Locations
binder - Connect multimeter to terminal 19 of relay socket and Ground (GND)
for voltage measurement.

Specification: approx. battery voltage
- Check wire connections.
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24-54
If specified value is obtained:

If no malfunctions are detected:
Check voltage supply for Fuel Pump (FP) and components - Check the following wire connection for open circuit and short circuit to
Ground (GND) and B+:
Central electric
in driver-side footwell, left, position 4
Terminal
VAG1598/31 test box


Socket
16 65
- Repair open circuit or short circuit if necessary.
- Replace Fuel Pump (FP) relay -J17-.
- Re-connect Engine Control Module (ECM).

- Remove fuses S228, S229, and S234 (positions 28, 29, and S234)
from fuse holder.
- Initiate output Diagnostic Test Mode Page 01
-56
and activate
Evaporative Emission (EVAP) canister purge regulator valve -N80-.
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