Electrical Testing, 1997 >

Electrical testing, 1997 >

NOTE:
- VAG1598 test box must not be connected to A/C control head -E87- when performing On Board Diagnostic with VAG1551 Scan Tool (ST)
- Further notes, test requirements, connecting adapter cables and test equipment VAG1598 Test Box, Connecting
- From m.y. 1997, do not connect VAG1598 test box to -E87- for test steps 1.1 through 5.7. (Test box only to be connected for test steps 5.8, 5.9 and 5.10).






Test No. 1 (A/C control head -E87- voltage supply, ground connection)










Test No. 2 (Temperature Sensors -G17-, -G56-, -G89-, G191-, G192-. )







Temperature sensor resistances (based on ambient temperature, resistance in k Ohms)







Test No. 3 (Fresh Air Blower -V2- and Control Module for Fresh Air Blower -J126-)










Test No. 4 (air/temperature distribution flap motors and related potentiometers)










NOTE:If DTC's for several flap motors are shown and malfunction is not determined in test 4, check wiring for short between individual flap motors (e.g. -V85- and -V70-, measured value between sockets 3 and 4 must be infinity Ohm).


Test No. 5 (A/C pressure switch -F129-, "A/C compressor intervention" signal, engine temperature signal from instrument cluster and Interior Temperature Sensor Fan -V42-)



















Test No. 6 (A/C Clutch Relay -J44-, actuation of Coolant Fan -V7- stage 1)







NOTE:
- Actuation of -V7- stage 2 via A/C pressure switch -F129-.
- The following test steps are only performed for A/C control heads -E87- with two displays:
- Test step 2.2 (the instrument panel interior temperature sensor -G56- is installed in A/C control heads -E87- with one display)
- Test step 5.7 (the interior temperature sensor fan -V42- is installed in A/C control heads -E87- with one display)













NOTE:
- Ignition key coding is transmitted to the A/C control head -E87- from the instrument cluster along with the coolant temperature and the signal "engine temperature too high" when ignition is switched on for vehicles as of m.y. 1999 (data message). Key coding can only be processed by A/C control heads -E87- with part number 8D0 820 043 after index "M." No information can be transmitted if the coolant temperature is too high.
- When ignition is switched on, A/C control head -E87- begins with the setting that was valid when the ignition was last switched off with this key (temperature, air distribution, fresh air blower RPM).
- The signal from instrument cluster (data message) cannot be checked with tools available.

List of changes to electrical tests, 1998