SEAT Workshop Service and Repair Manuals > Leon Mk1 > Power unit | 4LV Injection and Ignition System | Mixture preparation system, electronic inj.,Gas | Supplementary signals: testing | Signals from/to the air conditioning: testing

Test process

–	Connect the -V.A.G. 1551- (-V.A.G. 1552-). Start the engine and enter the “address code” 01 to select the engine control unit. (Fault reader: connecting and selecting the engine control unit → Chapter.)

Reading on display:

–	Press 0 and 8 for the function “Read measured value block” and confirm the entry with the Q key.

Rapid data transmission             HELP

Select function XX

Reading on display:

–	Press 0, 5 and 0 for “Display group number 50” and confirm the entry with the Q key.

Read measured value block           HELP

Enter display group no. XXX

Reading on display: (1...4 = display fields)

Watch the message in field 4. It should read Compr. NO

–	Activate the air conditioning.

–	Set to the lowest temperature and maximum blower speed.

The message on display field 4 should change to Compr. YES

–

Press →.

–	Press 0 and 6 for the function “End transmission” and confirm the entry with the Q key.

–	Switch off the ignition.

If the message does not change:

Read measured value block     50      →

–	Connect test box -V.A.G. 1598/31- to the wiring harness of the control unit, without connecting the engine control unit.

–	Test for open circuits in the wiring between test box female contacts 40 + 41 and the air conditioning system, following the wiring diagram. Wire resistance: 1.5 Ω max.

SEAT Workshop Service and Repair Manuals