1995 AUDI A8 air condition

24-164


Auxiliary signals, checking

Signal from A/C compressor, checking


Required special tools and test equipment

VAG1551 or VAG1552 Scan Tool (ST) with
VAG1551/3 adapter cable
VAG1598/22 test box
Multimeter US1119 (Fluke 83 or equivalent)
VW1594 connector test kit
Wiring diagrams

Test conditions
A/C functions OK
A/C is switched off
Vehicle at room temperature-above 15 C
(59 F)

No malfunctions stored in Diagnostic Trouble
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Continuation
If the displayed values are NOT OK:

- Connect VAG1598/22 test box to ECM harness
connector page 01
-67
.

- Check wiring for open circuit, short circuit to B+
or short circuit to Ground between ECM/test box
terminal 8 and either A/C control head -E87- or
Transmission Control Module (TCM).

Electrical Wiring Diagrams, Troubleshooting &
Component Locations binder If the wiring is OK:

- Check function of A/C control head -E87-.

Repair Manual, Heating & Air Conditioning,
Repair Group 01


- Carry out electrical testing of automatic
transmission.
Repair Manual, 5 Spd. Automatic
Transmission 01V, Repair Group 01
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24-168

Vehicle speed signal, checking


Required special tools and test equipment

VAG1551 or VAG1552 Scan Tool (ST) with
VAG1551/3 adapter cable
Multimeter US1119 (Fluke 83 or equivalent)
VW1594 connector test kit
Wiring diagrams

Test conditions
Vehicle Speed Sensor (VSS) OK; checking:

Repair Manual, Electrical Equipment, Repair
Group 90


Notes:

To check Vehicle Speed Sensor -G68-, the
vehicle must be driven. A second technician is
required to operate the scan tool during the
road test.
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Display fields

1 2 3 4
Display group 5: General engine data
Display xxx RPM xx.xx ms xxx km/h Idle
Part throt
Full throt
Decel
Enrich
Indicates Engine speed
(in 40 RPM
steps) Engine load Vehicle speed Operating
condition
Range 0 - 6800 RPM 0.00 - 12.75
ms 0 - 326 km/h ---
Specified
value --- --- Approx. vehicle speed ---

--- --- If no vehicle speed is displayed page 24
-171
,
Continuation
---
If displayed value is OK:

-
Press button.
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