Skoda OCTAVIA MK1 Service Manual page 249

t Vehicle system tester -V.A.G 1552 - with cable -V.A.G 1551/3-
t Measuring tool set -V.A.G 1594 A -
t Test box -V.A.G 1598/22-
Note
A positive signal is applied to contact 8 at the engine control unit by switching on the air
t
conditioning system.
The signal ensures the engine control unit maintains the idling at a constant speed given
t
power supply requirement differences in the air conditioning system.
Test condition
l Air conditioning system o.k.
l Auxiliary consumers (e.g. rear window heating) switched off
Connect vehicle system tester -V.A.G 1552- and select address word 01 "Engine
–
electronics". Engine idling.
Select 08 for the function "read measured value block" and further select display group
–
019.
For vehicles ► 07.97
The following appears in the display:
Display field 1: idling speed
Display field 3: signal of the air conditioning
system
Display field 4: condition of AC compressor
Switch on the air conditioning system. The
–
AC compressor must run.
Display field 3 must display "1".
Display field 4 must display "1"
(compressor on).
For vehicles 08.97 ►
The following appears in the display:
Display field 1: idling speed
Display field 3: signal of the air conditioning
system
Display field 4: condition of AC compressor
Switch on the air conditioning system. The
–
AC compressor must run.
Reading measured value block 19
->
850/rpm
Reading measured value block 19
->
850/rpm 0
Reading measured value block 19
->
850/rpm
249
0 0
1 1
0 0 00000000
0