Volkswagen Golf / Golf GTI / Jetta. Manual — part 226

24-158

Engine operating mode,
checking

Note:

The check establishes whether
Motronic Engine Control Module
(ECM) -J220- recognizes the engine
operating modes idling, overrun, part
throttle, wide open throttle and
enrichment.

Special tools and equipment

Note:

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

Test requirements

VAG 1551 Scan tool (or VAG

1552) with VAG 1551/3 adapter
cable

Engine Coolant Temperature

(ECT) must be at least 85 C,

display group 1, display zone

2.

Functions, checking

24-159

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.

Read measured value block

Input display group number XXX

Indicated on display:

- Press buttons -0-, -0- and -5- for "Display group

number 5" and confirm entry with -Q- button.

Read measured value block 5

1

2

3

4

Indicated on display: (1...4

display zones)

- Check whether control module recognizes

operating conditions (display zone 4):

Idling:

Idling must be displayed as long as the engine is

running at idle speed Display: Idling

Functions, checking

24-160

Part throttle:

- Rev up evenly.

As long as the engine is being revved up evenly,

part throttle must be displayed

Display: Part throt.

Enrichment:

- Floor accelerator pedal (onto throttle valve limit

stop).

Acceleration enrichment must be displayed

briefly

Display: Enrich.

Overrun mode:

- Increase engine speed to above 3000 rpm.

- Close throttle valve abruptly.

Display: Overrun

Note:

A road test may have to be performed to show

"Overrun" in display.

Observe the valid safety precautions when

performing a road test

Page 24-33

.

Functions, checking

24-161

Wide open throttle:

- Floor accelerator pedal (onto throttle valve limit

stop).

Full load must be displayed briefly

Display: Full load

Note:

A road test may have to be performed to show

"Full load" in display.

Observe the valid safety precautions when

performing a road test

Page 24-33

.

- Press

button.

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

output" and confirm entry with -Q- button.

If the specifications are not obtained:

- Check DTC memory, repair malfunctions if

necessary and then erase DTC memory

Page

01-23

.

- Check Throttle Valve Control Module -J338-

Page 24-59

.

- Read readiness code

Page 01-146

. If DTC

memory has been erased or Motronic Engine
Control Module (ECM) -J220- was disconnected
from battery positive (B+), readiness code must
be generated again

Page 01-149

.

Functions, checking