YH4
GRAND
VITARA
AIR CONDITIONING (OPTIONAL) 1B-7
ConditionPossible CauseCorrection
Cool air does not come
out or insufficient
cooling (A / C system
normal operative)Compressor faulty
Air in A / C system
Air leaking from cooling unit or air
duct
Heater and ventilation system faulty
Blower motor faulty
Excessive compressor oil existing in
A / C systemCheck compressor.
Replace condenser dryer, and
evacuation and charging.
Repair as necessary.
Check blower unit.
Check heater control lever assembly.
Check heater assembly.
Check blower motor.
Pull out compressor oil in A / C system
circuit, and replace compressor.
Cool air does not comes
out only intermittentlyWiring connection faulty
Expansion valve faulty
Excessive moisture in A / C system
A / C controller faulty
Magnetic clutch faulty
Excessive charge of refrigerantRepair as necessary.
Check expansion valve.
Replace condenser dryer, and
evacuation and charging.
Check A / C controller.
Check magnetic clutch.
Check charge of refrigerant.
Cool air comes out only
at high speedsCondenser clogged
Insufficient charge of refrigerant
Air in A / C system
Drive belt slipping
Compressor faultyCheck condenser.
Check charge of refrigerant.
Replace condenser dryer, and
evacuation and charging.
Adjust or replace drive belt.
Check compressor.
Cool air does not comes
out only at high speedsExcessive charge of refrigerant
A / C evaporator frostedCheck charge refrigerant.
Check A / C evaporator.
Check A / C thermistor.
Insufficient velocity of
cooled airA / C evaporator clogged or frosted
Air leaking from cooling unit or air
duct
Blower motor faulty
Wiring or grounding faultyCheck A / C evaporator.
Repair as necessary.
Check blower motor.
Repair as necessary.
YH4
GRAND
VITARA
3. Bubbles
1B-10 AIR CONDITIONING (OPTIONAL)
QUICKLY CHECKING OF REFRIGERANT
CHARGE (IF EQUIPPED WITH SIGHT GLASS)
CHARGE OF REFRIGERANT
The following procedure can be used for quickly checking whether
the A / C system has a proper charge of refrigerant or not.
Run engine at fast idle, and operate A / C at its max. cooling capacity
for a few minutes. Then, look at the sight glass (1) on receiver / dryer
(2) and compare what is observed with the symptoms listed in
ªCHECKING REFRIGERANT CHARGEº table given below.
CHECKING REFRIGERANT CHARGE
CONDITIONPOSSIBLE CAUSESCORRECTION
Bubbles observed in sight glassInsufficient charge of refrigerant in
systemCheck system for leaks with a leak
tester.
No bubbles observed in sight glassNo charge or proper or too much
charge of refrigerant in systemRefer to the following item.
No temperature difference
between compressor inlet and
outletEmpty or nearly empty systemRecovery, evacuate and charge
system and then check it for leaks
with a leak tester.
Noticeable temperature difference
between compressor inlet and
outletProper or too much charge of
refrigerant in systemRefer to the following item.
When A / C is turned OFF,
refrigerant in sight glass clears
immediately and remains clearToo much charge of refrigerant in
systemDischarge excess charge of
refrigerant to adjust it to a specified
charge.
When A / C is turned OFF,
refrigerant in sight glass once
produces bubbles and then clearsProper charge of refrigerant in
systemNo correction needed because
charge of refrigerant is normal.
YH4
GRAND
VITARA
AIR CONDITIONING (OPTIONAL) 1B-11
COMPRESSION SYSTEM DIAGNOSIS
Compressor troubles are mainly following three types: gas leakage, noise and insufficient pressure.
Compressor gas leakages in most cases develop from the shaft seal. When detecting gas leakage, always use
a leak tester. If a small amount of oil seeps out from the shaft seal, there is no necessity of replacing the seal. The
shaft seal has been designed to allow a small amount of oil to leak out for lubricating purpose. Thus, the shaft seal
should be replaced only when a large amount of compressor oil is leaking out or when gas leakage is discovered
by using gas tester.
In regard to noise and insufficient pressure, repairs should be made only after diagnosing the trouble properly.
CONDITION
POSSIBLE CAUSESCORRECTION
Noise from compressorDefective bearing
Defective cylinder and / or shaftReplace.
Replace.
Noise from magnetic clutchDefective bearing
Defective clutch faceReplace.
Replace.
Insufficient coolingDefective gasketReplace.
Defective reed valveReplace.
Not rotatingLocked compressor
Seized magnetic clutch
Rotating parts seized by insufficient oil
amountReplace.
Replace.
Replace.
Oil and / or gas leakageDefective seal
Defective O-ringReplace.
Replace.
YH4
GRAND
VITARA
1B-14 AIR CONDITIONING (OPTIONAL)
HIGH PRESSURE CAUGE LOW PRESSURE GAUGE THERMOMETER AT
CENTER DUCT
Insufficient
cooling of
condenser
PERFORMANCE DIAGNOSIS TABLE
TESTING RESULTSPOSSIBLE CAUSEREMEDY
Pressure high
(ªAº area of high side
graph)Refrigerant overcharged
Expansion valve frozen or clogged
Clogged refrigerant passage of high side
Condenser fan malfunction
Dirty or bent condenser fins
Compressor malfunction (Insufficient oil etc.)
Engine overheatRecharge
Check expansion valve
Clean or replace
Check condenser fan
Clean or repair
Check compressor
Check engine cooling
system
Pressure low
(ªBº area of high side
graph)Insufficient refrigerant (Insufficient charge or
leakage)
Expansion valve malfunction (Valve opens too
wide)
Compressor malfunction (Insufficient
compression)Check for leakage, repair if
necessary and recharge
Check expansion valve
Check compressor
Pressure high
(ªAº area of low side
graph)Expansion valve malfunction (Valve opens too
wide)
Compressor malfunction (Insufficient
compression)Check expansion valve
Check compressor
Pressure low
(ªBº area of low side
graph)Insufficient refrigerant (Insufficient charge or
leakage)
Expansion valve malfunction (Valve opens too
narrow)
Clogged refrigerant passage (Crashed pipe)Check for leakage, repair if
necessary and recharge
Check expansion valve
Repair or replace
Outlet air temperature
at center duct is high
(Crossing point is in
area ªAº)Insufficient or excessive charge of refrigerant
Dirty or bent evaporator fins
Air leakage from cooling (heater) unit or air
duct
Malfunctioning, switchover function of damper
in cooling (heater) unit
Compressor malfunctionCheck refrigerant
pressure
Clean or repair
Repair or replace
Repair or replace
Check compressor
Outlet air temperature
at center duct is low
(Crossing point is in
area ªBº)Insufficient air volume from center duct
(Heater blower malfunction)
Compressor malfunctionCheck blower motor and
fan
Check compressor
NOTE:
If ambient temperature is within 30 ± 35C (85 ± 95F), it is possible to do using next page table for more
detail diagnosis.
YH4
GRAND
VITARA
AIR CONDITIONING (OPTIONAL) 1B-15
AMBIENT TEMPERATURE WITHIN 30 ± 35C (85 ± 95F)
CONDITION
MANIFOLD
GAUGEMPa
(kg/cm2)
(psi)DETAILCAUSECORRECTION
LoHi
0.23 ± 0.35
(2.3 ± 3.5)
(33 ± 50)1.4 ± 1.75
(14 ± 17.5)
(200 ± 249)
Normal condition.ÐÐÐÐ
Negative
pressure0.5 ± 0.6
(5 ± 6)
(71.2 ± 85.3)
The low pressure side
reads a negative pressure,
and the high pressure side
reads an extremely low
pressure.
Presence of frost around
tubing to and from receiver /
dryer and expansion valve. Dust particles or water
droplets are either stuck or
frozen inside expansion
valve, preventing the
refrigerant from flowing.Clean expansion valve.
Replace it if it cannot be
cleaned.
Replace receiver / dryer.
Evacuate the A / C
system and recharge
with fresh refrigerant.
Normal:
0.23 ± 0.35
(2.3 ± 3.5)
(33 ± 50)
Abnormal:
Negative
pressureNormal:
1.4 ± 1.75
(14 ± 17.5)
(200 ± 249)
Abnormal:
0.69 ± 0.98
(7 ± 10)
(100 ± 142) During A / C operation, the
low pressure side
sometimes indicates
negative pressure, and
sometimes normal
pressure. Also high
pressure side reading
fluctuates between the
abnormal and normal
pressure.Expansion valve is frozen
due to moisture in the
system, and temporarily
shuts off the refrigeration
cycle.Replace expansion
valve.
Replace receiver / dryer.
Evacuate A / C system
and recharge with fresh
refrigerant.
0.05 ± 0.15
(0.5 ± 1.5)
(4.2 ± 21.3)
0.69 ± 0.98
(7 ± 10)
(100 ± 142)
Both low and high pressure
sides indicate low readings.
Continuous air bubbles are
visible through sight glass.
Output air is slightly cold.Insufficient refrigerant in
system. (Refrigerant
leaking)Using a gas leak
detector, check for leaks
and repair as necessary.
Recharge refrigerant to a
specified amount.
If the pressure reading is
almost 0 when the
manifold gauges are
attached, check for any
leaks, repair them, and
evacuate the system.
0.4 ± 0.6
(4 ± 6)
(56.9 ± 85.3)
Pressure on low pressure
side is high.
Pressure on high pressure
side is low.
Both pressure becoming
equal right after A / C is
turned OFF.Internal leak in compressor.Inspect compressor and
repair or replace as
necessary.
035 045
High pressure reading on
both low and high pressure
sides.
Air bubbles are not visible
even when engine rpm is
lowered.Overcharged A / C system.
Faulty condenser cooling
operation.
Faulty condenser fan
operation.Adjust refrigerant to
specified amount.
Clean condenser.
Inspect and repair
condenser fan.
0.35 ± 0.45(3.5 ± 4.5)
(50 ± 64)
1.96 ± 2.45
(20 ± 25)
(285 ± 355)
High pressure reading on
both low and high pressure
sides.
Low pressure side tubing is
not cold when touched.
Air bubbles are visible
through sight glass.Presence of air in A / C
system. (Improperly
evacuated)Replace receiver / dryer.
Inspect quantity of
compressor oil and
presence of
contaminants in oil.
Evacuate system and
recharge with fresh
refrigerant.
0.45 ± 0.55
(4.5 ± 5.5)
(64 ± 78)
High pressure reading on
both low and high pressure
sides.
Large amount of frost or
dew on the low pressure
side tubing.Faulty expansion valve.
Refrigerant flow is not
regulated properly.Replace expansion
valve.
YH4
GRAND
VITARA
3
1B-34 AIR CONDITIONING (OPTIONAL)
5) Disconnect coupler from dual pressure switch (1).
6) Disconnect condenser outlet pipe (3).
7) Disconnect condenser cooling fan motor coupler (2).
8) Remove condenser with fan.
NOTE:
Be careful not to damage fins of condenser and radiator.
9) Remove A / C condenser cooling fan assembly from condenser.
INSTALLATION
Reverse removal sequence to install condenser, noting following
point.
1) When replacing condenser, add 20 to 30 cc of refrigerating oil
from compressor suction-side.
2) Evacuate and charge system according to previously-described
procedure.
YH4
GRAND
VITARA
1
1. Ears1. Air flow
1B-38 AIR CONDITIONING (OPTIONAL)
CLEAN
Blow off dust by compressed air from air outlet side of the filter ele-
ment.
INSTALLATION
Reverse removal procedure for installation noting the followings:
Install filter into cooling unit directing arrow mark on its end face
to heater unit.
Enable air bag system after installation. Refer to ªENABLING AIR
BAG SYSTEMº in Section 10B.
YH4
GRAND
VITARA
AIR CONDITIONING (OPTIONAL) 1B-39
COOLING UNIT (EVAPORATOR)
REMOVAL
1) Disconnect negative (±) cable at battery.
2) Disable air bag system. Refer to ªDisabling Air Bag Systemº in
Section 10B.
3) Recover refrigerant by using recovery and recycling equipment.
Be sure to follow the instruction manual for the equipment.
The amount of compressor oil removed must be measured and
the same amount added to the system.
4) For G16 and J20 engine
Disconnect suction pipe (1), and liquid pipe (2) from evaporator
(cooling unit).
CAUTION:
As soon as above hose and pipe are disconnected, cap
opened fittings so that moisture and dust may not enter
cooling unit.
5) Remove blower motor unit. Refer to Section 1A ªHEATER AND
VENTILATIONº.
6) Disconnect thermistor wire coupler.
7) Remove cooling unit (evaporator).
DISASSEMBLY (FOR CAMI PRODUCTION VEHICLE)
1) Remove filter (2) from cooling unit (3) assembly by removing fil-
ter cover (1).
2) Remove screws (1) to separate evaporator upper and lower
cases from each other.