check engine light AUDI A6 1995 C5 / 2.G ATQ Engine Motronic Injection System Servicing Workshop Manual

24-20


Important note:
After re-connecting the Engine Control Module (ECM), the following work
steps must be performed:
- Check DTC memory and erase it if necessary Page 01
-15
.
- Perform adaptation of the Throttle Valve Control Module -J338- Page
24
-142
.
Note:
In the first adaptation phase during engine basic setting, it is possible that
idle will be rough and vehicle may shake lightly in drive mode. - Connect VAG1598/31 test box to connector of wiring harness. Ground
(GND) clip at test box (not visible in illustration) must be connected to
Ground (GND). Relevant test procedures note whether Engine Control
Module (ECM) should also be connected to the test box.
- Perform test as described in relevant repair sequence.
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- Observe notes for coding new Engine Control
Module (ECM) Page 01
-71
.
- For vehicles with cruise control (discernable at
steering column), switch this free in ECM:

Repair Manual, Electrical Equipment, Repair
Group 01; On Board Diagnostic (OBD) of cruise control system; Cruise control system, checking

- Adapt immobilizer to Engine Control Module
(ECM):

Repair Manual, Electrical Equipment, Repair
Group 01; On Board Diagnostic (OBD) of immobilizer after replacing Engine Control Module (ECM)

- For vehicles with automatic transmission, the
kick down function must be learned Page 24
-
161
.
- Generate readiness code Page 01
-82
.

Note:
In the first adaptation phase during engine basic
setting, it is possible that idle will be rough and
vehicle may shake lightly in drive mode.
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Checking voltage supply

Test requirements:

Fuel Pump (FP) OK, checking Page 24
-
49
.

Fuse for fuel injectors OK

Electrical Wiring Diagrams, Troubleshooting &
Component Locations binder

- Disconnect harness connector at the fuel
injector to be tested.

If LED does not light up: - Connect VAG1527B voltage tester as follows:Harness connector
Terminal
Measure to
1 Engine Ground (GND)
- Switch ignition on.

LED must light up.
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- Repair open circuit if necessary.
If LED lights up:

Checking activation

Test requirement:

Internal resistance of valve OK

Note:
Voltage testers do not go out completely during low current pick-up
between activations by the ECM, but rather continue to glow a little and
then get slightly brighter during activation. - Slide back rubber grommet of fuel injector connector (arrow), but leave
connector connected.
- Connect VAG1527B voltage tester between sockets 2 (signal) and 1
(B+).
- Operate starter briefly (engine can also start).

LED must blink.
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- Disengage retaining clip and remove fuel
injector.

Note:
Fuel lines must be disconnected before replacing
fuel distributor.
Installation is reverse of removal, noting the
following:

Remove O-rings at all opened connections.
(Never remove plastic cap from valve head
to replace front O-ring - pry O-ring off over
plastic cap).
Lightly lubricate O-rings with clean engine
oil.
Make sure fuel injectors are in place and
seated correctly
Check clip for unobstructed fitting.
Place fuel rail with secured fuel injectors
onto intake manifold, and apply uniform
pressure to press it in.

Tightening torque
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