Refrigerant Temperature Sensor G454 , Removing And Installing - Audi Q7 2007 Repair Manual

15.5 Refrigerant Temperature Sensor -
G454- , Removing and Installing
Removing
Note
The Refrigerant Temperature Sensor - G454- was discontin‐
♦
ued from 11/2007 as a running change. On vehicles with the
"Comfort" A/C system, make sure the Climatronic Control
Module - J255- front A/C control head for the "Comfort" A/C
system is installed. Vehicles with a 6-cylinder TDI engine, an
8-cylinder engine or a 12-cylinder TDI engine but without a
Refrigerant Temperature Sensor - G454- may only have the
"Comfort" front A/C control head installed (part number "4L0
820 043", beginning with index letter "K"). Refer to the Parts
Catalog and Use the Vehicle Diagnostic Tester via the "Guided
Fault Finding" function.
If the vehicle has the "Basis" A/C system without a Refrigerant
♦
Temperature Sensor - G454- , and the sensor -G454- is being
displayed as a fault, then perform an adaptation to the "Basis"
front A/C control head. It is not necessary to perform this on
the "Comfort" A/C system because it has different versions of
the front A/C control head. On vehicles with the "Basis" A/C
system, "Guided Fault Finding" displays the fault missing Re‐
frigerant Temperature Sensor - G454- and the evaluating of
the refrigerant temperature sensor -G454- switches off (by en‐
tering "adaptation"). Use the Vehicle Diagnostic Tester via the
"Guided Fault Finding" function.
The measured value from the Refrigerant Temperature Sen‐
♦
sor - G454- is not evaluated by the Climatronic Control Module
- J255- front A/C control head ("adaptation" has shut off the
evaluating). The missing refrigerant temperature sensor -
G454- will be stored as a fault because the vehicle is supposed
to have a refrigerant temperature sensor -G454- (solution:
change the adaptation to "Basis" front A/C control head. Use
the Vehicle Diagnostic Tester via the "Guided Fault Finding"
function. Or, if the vehicle has a "Comfort" front A/C control
head, for example, connect a refrigerant temperature sensor
-G454- , which is OK, to the vehicle wiring harness and secure
it to the vehicle (without removing the faulty refrigerant tem‐
perature sensor -G454- and installing a new refrigerant tem‐
perature sensor -G454- ).
The Refrigerant Temperature Sensor - G454- -2- is inside the
♦
refrigerant line in front of the engine on vehicles with an 8-
cylinder TDI engine.
WARNING
♦ The connection for Refrigerant Temperature Sensor -
G454- is not equipped with valve
♦ Refrigerant must be extracted from refrigerant circuit be‐
fore removing Refrigerant Temperature Sensor - G454- .
If Refrigerant Temperature Sensor - G454- is not removed
within 10 minutes after extraction, pressure may build up
in refrigerant circuit by renewed evaporation. Extract the
refrigerant once more.
– Discharge the refrigerant circuit. Refer to ⇒ A/C System with
Refrigerant R134a; Rep. Gr. 87 ; Refrigerant Circuit (A/C Sys‐
tem with Refrigerant R134a; Refrigerant Circuit, Using Service
Station).
Heating, Ventilation and Air Conditioning - Edition 04.2013
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Audi Q7 2007 ➤
15. Refrigerant Circuit, Servicing
255