Term(s) Abbreviation Definition Previously used
(if applicable) term(s) (or Eng-
lish Equivalent)
T
tachometer
Thermal Vacuum Valve
Three
-way Catalytic Converter
Three
-way + Oxidation Catalytic
Converter TWC + OC
Throttle
------I
Throttle Body TB
Throttle Position TP
Throttle Position Sensor TPS
throw
-out bearing
throw
-out fork
tie
-rod (steering)
timing
tire
top dead center TDC
torque converter
Transmission
Transmission Control Module
Transmission Control Switch
Transmission Oil Temperature TOT
Transmission Range TR
I Transmission Speed Sensor TSS
tread
trunk
turn indicator, turn signal lamp
two cycle a
circuit that provides input for an electronic
tachometer display
controls vacuum levels or routing based on
temperature
catalytic converter that reduces the levels of
HC,
CO & NOx
catalyticconverter systemthat has both TWC
and OC. Usually secondary air is introduced
between the two catalvsts
procedure whereby the performance of a
product is measured under various
conditions - - . -. . . - . . -
a valve for regulating the supply of a fluid,
usually air or an aidfuel mixture, to an engine
device containing the throttle
interprets throttle position and movement to
identify idle, acceleration and full
-power
demands
relationship between spark plug firing and
piston position, usually expressed
in crankshaft degrees BTDC or ATDC of the
compression stroke
device which, by its design, multiplies the
torque in a fluid coupling between an engine
and transmission
device which selectively increases or
decreases the ratio of relative rotation
between its
inDut and outDut shafts
controls the shifting pattern of the
(automatic) transmission
Modifies the operation of electronically
controlled transmissions
indicates temperature
of transmission fluid
the range in which the transmission is
operating
indicates rotational speed of transmission
output shaft or turbine
shaft
track between tire contact centers; not to be
confused with tire contact tread pattern
principle of engine which fires every second
stroke of the piston cat
cat, dual bed
Throttle poten
-
tiometer, TPS, TP
clutch release
bearing
clutch release
lever
track rod
tvre
TCC, CCC, CCO,
LUS, MLUS,
MCCC
transmission
ECU
track boot, luggage
compartment
direction indica
- tor
two stroke
Issue 1 August 1994 26 X300 VSM
Climate Control Systems
14.8 REFRIGERATION CYCLE:
The Compressor draws low pressure, low temperature re- frigerant from the evaporator and by compression, raises re- frigerant temperature and pressure. High pressure, hot
vaporized refrigerant enters the Condenser where it is
cooled by the flow of ambient air.
A change of state occurs
as the refrigerant cools in the condenser and it becomes a
reduced temperature high pressure liquid.
From the condenser the
liquid passes into the Receiver / Drier which has three functions,
a) Storage vessel for varying system refrigerant demand.
b) Filter to remove system contaminants. c) Moisture removal via the dessicant.
With the passage through the
receiver/drier completed the,
still high pressure liquid refrigerant enters the Expansion
Valve where it is metered through a controlled orifice which
has the effect of reducing the pressure and temperature.
The refrigerant, now
in a cold atomized state, flows into the
evaporator and cools the air which is passing through the
matrix.
As heat is absorbed by the refrigerant
it once again changes
state, into a vapour, and returns to the compressor for the
cycle to be repeated (Fig.
1).
There is an automatic safety valve incorporated in the com- pressor which will operate should the system pressure be in
excess of 41 bar. The valve will reseat when the pressure
drops below 27,6 bar.
W Thedivisionof HIGHandLOWsideissimplythesys- tem pressure differential created by the compressor
discharge (pressure), suction (inlet) ports and the
relative inlet and outlet ports
ofthe expansion valve.
This differential is critical to system fault diagnosis
and efficiency checks.
Twelve Cylinder Vehicles only:
Dual pressure switch: This two-function pressure switch
cuts electrical power to the compressor clutch if the system
pressure is outside of the range
of 2 Bar (1st Function) to 30
Bar (2nd Function).
Six Cylinder Vehicles only:
There are two switches incorporated into the high side of the
system which have the following functions:
a) Trinary; This three function pressure switch, cuts electri
-
cal power to the compressor clutch should the system pres- sure not be in a range of 2 bar (1st function) to 30 bar (2nd
function). The switch also provides a ground signal to oper
- ate the appropriate relay (within the 'Stribel,' unit) to ener- gize both engine cooling fans when maximum A/ C cooling
is required. Operation pressure, 20 bar input (3rd function).
b) Pressure Switch Slow Cooling Fans; When the system
pressure is 12 bar, medium A/ C demand, the operation of
this switch connects both engine cooling fans in series to op- erate at half battery voltage and so, half fan speed. 1.
Compressor
2. Condenser
3. Receiver / Drier 4. Expansion Valve
5. Evaporator
6. Pressure switch - Dual type
on 12
cyl & Trinary on 6 cyl
Fig. 1
0
0
Issue 1 August 1994 12 X300 VSM
