Volkswagen Golf / Golf GTI / Jetta. Manual — part 217

24-122

Test sequence

- Connect VAG 1551 Scan tool (or VAG 1552)

and select engine electronics control module
with "Address word" 01. Engine must be running
at idle speed: ((VAG 1551 and Motronic Engine
Control Module (ECM) -J220-, connecting and
selecting

Page 01-12

).

Rapid data transfer

HELP

Select function XX

Indicated on display:

- Press buttons -0- and -8- for function "Read

measured value (data) block" and confirm entry
with -Q- button.

Components, checking

24-123

Read measured value block

Input display group number XXX

Indicated on display:

- Press buttons -0-, -0- and -1- for

"Display group number 1" and
confirm entry with -Q- button.

Read measured value block 1

1

2

3

4

Indicated on display: (1...4

display

zones)

If the engine speed or the Oxygen
Sensor control do not change:

- Check whethe Engine Coolant

Temperature (ECT) is above 85

C in display zone 2.

- Observe engine speed in display

zone 1 and Oxygen Sensor
control before Three Way
Catalytic Converter (TWC) in
display zones 3 and 4.

- Observe engine speed in display

zone 1 and Oxygen Sensor
control before Three Way
Catalytic Converter (TWC) in
display zone 3.

- Systematically spray parts of

intake system with engine leak
detector spray.

- Press

button.

- Press buttons -0- and -6- for

function "End output" and confirm
entry with -Q- button.

- Switch off ignition.

Components, checking

24-124

If the engine speed drops or the Oxygen Sensor

control changes:

- Press

button.

- Press buttons -0- and -6- for function "End

output" and confirm entry with -Q- button.

- Switch off ignition.

- Check sprayed areas of intake system for leaks

and correct if necessary.

Components, checking

24-125

Functions, checking

Idle speed check

Note:

Idle speed, ignition timing and CO content not

adjustable.

The idle speed is regulated to specification by

the throttle valve positioner in conjunction with
the DIS function.

CO content regulated to specification by

Oxygen Sensor control. Malfunctions in Oxygen
Sensor control are detected by On Board
Diagnostic (OBD) and stored in DTC memory.

Special tools and equipment

Note:

All functions which could previously be performed
with VAG 1551/1552 can also be performed with
the VAS 5051.

VAG 1551 Scan tool (or VAG 1552) with VAG

1551/3 adapter cable

Functions, checking