Audi A3 1997 Manual page 73

Notes:
◆ Depending on high-pressure sensor -G65 signal, radiator fan control unit -J293:
- indicates to operating and display unit -E87 that the refrigerant circuit pressure is OK and the compressor
can be switched on (via magnetic clutch -N25).
- switches radiator fan to 2nd speed if pressure increases.
◆ If code 1 "pressure switch -F129 open" is displayed in measured value block 1 as a compressor shutoff
criterion:
- Use current flow diagram to check the wiring to -G65 for a loose contact.
- Use current flow diagram to check wiring between control unit -J293 and -E87 for loose contact.
- Check the actuation of the radiator fan -V7 speed 1 (=>Final control diagnosis, Page
Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
- Check signal from high-pressure sensor -G65 =>Page
Voltage tester V.A.G 1527,
Operating and display unit connected to the test box (adapter cable V.A.G 1598/11 and /12)
- Adapter cable V.A.G 1598/11 connected
Test step V.A.G 1598
socket
5.2 Earth
and
6
Notes:
◆ Earth applied e.g. to connector D contact 14.
◆ Brief flickering of the LED in the voltage tester indicates that the dash panel insert is transmitting a temper‐
ature signal.
◆ The assignment of the ignition key is transmitted to the -E87 through the dash panel insert together with the
refrigerant temperature and the signal "engine temperature too high" when ignition is switched on (data
telegram). If the refrigerant temperature is too high, no information may be transmitted.
◆ The assignment of the ignition key can only be recognised and therefore transmitted by the dash panel insert
on vehicles fitted with an immobiliser.
◆ When the ignition is switched on, the -E87 starts with the setting which was valid the last time the ignition
was switched off with this key (temperature, air distribution, fresh air blower speed).
◆ The signal from the dash panel insert (data telegram) cannot be checked with workshop tools.
=> Electrical System; Repair group 90; Repair dash panel insert Repair dash panel insert
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
Testing of
Signal "Engine
temperature too
high"
10.4 - Checking in vehicles with an operating and display unit with one display
Heating, Air Conditioner - Edition 06.2000
85 .
▪ Test conditions Specified value
- Additional opera‐
tions
▪ Engine running ▪ LED in the voltage
tester flickers briefly.
Audi A3 1997 ➤
18 ).
Remedies if speci‐
fied value not at‐
tained
- Use the current
flow diagram to lo‐
cate and rectify short
to earth.
Rectify the air condi‐
tioner compressor
shutoff condition in
the dash panel in‐
sert.
67