Audi A8 1994 - Page 79

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2.2.2 A/C Compressor Speed Sensor -G111-
Inductive sensor
The sensor pulses (4 per compressor revolution) and the engine
speed enable the Front A/C display control head -E87- or the Cli‐
matronic Control Module -J255- to calculate belt slip.
If the belt slip exceeds a specified value, the compressor is
switched off by the control module via the A/C clutch.
Note
♦ Installing in Audi vehicles with an A/C compressor driven by a
ribbed belt and with Zexel compressor. Refer to ⇒ Heating
and Air Conditioning; Rep. Gr. 87 ; Description and Operation
(vehicle-specific repair manual).
♦ Beginning the production year 2006, the name of the Zexel A/
C compressor was changed from Zexel to Valeo.
2.2.3 A/C Pressure Switch -F129-
This pressure switch has 3 functions
1. Switches the coolant fan to the next higher level when the
pressure in the refrigerant circuit increases (approximately 16
bar).
2. Switches off A/C system if pressure is excessive (approximate‐
ly 32 bar), for example, because of insufficient engine cooling.
3. Switches off A/C system if pressure is insufficient (approxi‐
mately 2 bar), for example, loss of refrigerant.
Note
A/C Pressure Switch -F129- replaces the A/C Refrigerant High
Pressure Switch -F23- , A/C Refrigerant Low Pressure Switch -
F73- and the A/C Refrigerant High Pressure Switch -F118- .
Audi 100 1991 ➤ , Audi 80 1992 ➤ , Audi A1 2011 ➤ , Audi A2 2001 ➤ , A ...
Refrigerant R134a Servicing - Edition 01.2011
2. Description and Operation 75