Volkswagen Workshop Service and Repair Manuals > Golf Mk4 > Power unit | Direct injection and preglow system with distributor-type pump to 04.99 | Self diagnosis, V.A.G Inspection Service | Self-diagnosis | Connecting fault reader V.A.G 1551 and selecting engine electronics control unit

Connecting fault readerV.A.G 1551 and selecting engine electronics control unit

Connecting fault reader -V.A.G 1551- and selecting engine electronics control unit

Special tools and workshop equipment required

t	Fault reader -V.A.G 1551-

t	Diagnosis cable -V.A.G 1551/3-

Note

Instead of fault reader -V.A.G 1551-, vehicle system tester -V.A.G 1552- can also be used, though a print-out is not possible.

Test prerequisite

l	Fuses in relay plate fuse holder -S12- OK

l	The battery voltage must be at least 11.5 V.

l	Earth connections between engine (on gearbox bell housing) and body (beneath battery) OK.

Procedure

–	Pull cover -1- off in direction of arrow.

–	Connect fault reader -V.A.G 1551- with diagnosis cable -V.A.G 1551/3-.

When the fault reader has been connected:

–	Depending upon desired function: switch ignition on or start engine → Chapter, “Selectable functions” table.

Note

t	If the display remains blank, check voltage supply to diagnosis connection → Current flow diagrams, Electrical fault finding and Fitting locations

t	If the display does not indicate as described in the work sequence: → Fault reader operating instructions

t	If due to an input fault “fault in the data transfer!”is displayed, pull wire off fault reader, reconnect and repeat work step.

–	Operate fault reader taking into account the information on the display:

Indicated on display:

V.A.G SELF-DIAGNOSIS                HELP

 1 - Rapid data transfer*

Indicated on display:

¹⁾	Appears alternately

–	Operate fault reader taking into account the information on the display:

–	Press button 1 for “Rapid data transfer”.

–	Press buttons 0 and 1 for address word “Engine electronics” and confirm the input with Q button.

V.A.G SELF-DIAGNOSIS                HELP

 2 - Flash code output*

The fault reader -V.A.G 1551- display will show the control unit identification, e.g.:

t	038906018D = Part no. of control unit (for up-to-date control unit version see parts catalogue)

t	1.9 L = Engine displacement

t	R4 = Type of engine (4-cyl. in-line engine)

t	EDC = Injection system (Electronic Diesel Control)

t	G = Vehicles with cruise control system (no display = no cruise control system)

t	SG = Gearbox type: manual gearbox (AG = automatic gearbox)

t	1817 = Control unit software version

t	Coding 00000 = Coding variant

t	WSC xxxxx = Workshop code from fault reader -V.A.G 1551- with which coding was last carried out. (If the factory coding has not been changed, WSC 00000 appears)

–	Press → button.

038906018D  1.9L  R4  EDC  GSG    1817->

Coding 0000                     WSC00000

Indicated on display:

–	Further measures see repair procedures.

Rapid data transfer                 HELP

Select function XX

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