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
1B-8 AIR CONDITIONING (OPTIONAL)
DIAGNOSIS OF ABNORMAL NOISE
There are various types of noise, ranging from those produced in the engine compartment to those from the pas-
senger compartment, also from rumbling noises to whistling noises.
ABNORMAL NOISE FROM COMPRESSOR
ConditionPossible CauseCorrection
During compressor operation, a
rumbling noise is heard
proportional to engine
revolutions.Inadequate clearance in piston
area (piston or swash-plate).Repair or replace compressor as
necessary.
A loud noise is heard at a certain
rpm, disproportionately to engine
revolution.Loose or faulty V-belt.
Loose mounting bolts.Adjust V-belt tension, or
replace belt.
Retighten mounting bolts.
A loud rattle is heard at low
engine rpm.Loose compressor center bolt.Retighten center bolt.
Replace compressor if it was
operated in this condition for a
long time.
ABNORMAL NOISE FROM MAGNETIC CLUTCH
ConditionPossible CauseCorrection
A rumbling noise is heard when
compressor is not operating.Worn or damaged bearings.Replace bearings.
A chattering noise is heard when
compressor is engaged.Faulty clutch gap (excessive).
Worn clutch friction surface.
Compressor oil leaked from shaft
seal, contaminating the friction
surface.Adjust clutch gap.
Replace clutch.
Replace compressor shaft oil
seal.
ABNORMAL NOISE FROM TUBING
ConditionPossible CauseCorrection
A droning noise is heard inside
vehicle, but not particularly
noticeable in engine
compartment.Faulty tubing clamps.
Resonance caused by pulsation
from variations in refrigerant
pressure.Reposition clamps or increase
the number of clamps.
Attach a silencer to tubing, or
modify its position and length.
ABNORMAL NOISE FROM CONDENSER
ConditionPossible CauseCorrection
Considerable vibration in
condenser.Resonance from condenser
mounting stay and body.Firmly insert a silencer between
condenser mounting stay and
body.
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
For CAMI production vehicle
For IWATA production vehicle
1B-12 AIR CONDITIONING (OPTIONAL)
PERFORMANCE DIAGNOSIS
1) Confirm that vehicle and environmental conditions are as fol-
lows.
Vehicle is not exposed to direct sun.
Ambient temperature is within 15C ± 35C (59F ± 95F).
2) Make sure that high pressure valve (1) and low pressure valve
(2) of manifold gauge are firmly closed.
3) Connect high pressure charging hose (3) to high pressure ser-
vice valve (5) on vehicle, and connect low pressure charging
hose (4) to low pressure service valve (6) on vehicle.
4) Bleed the air in charging hoses (3), (4) by loosening their respec-
tive nuts on manifold gauge, utilizing the refrigerant pressure.
When a hiss is heard, immediately tighten nut.
CAUTION:
Do not interchange high and low pressure charging
hoses by mistake.
5) Warm up engine to normal operating temperature (engine cool-
ant temperature at 80 ± 90C (176 ± 194F)) and keep it at spe-
cified idle speed. (Radiator cooling fan should not be working
when checking pressure and temperature.)
6) Turn A / C switch ON, and set blower switch at ªHIº (4th position),
temperature control knob at ªCOOLº, air outlet control knob at
ªFACEº, fresh / circulation control knob at ªCIRCULATIONº.
(Confirm that A / C compressor and condenser fan are working.)
7) Keep all windows, doors and engine food open.
Ambient temperature
15 ± 35C (59F ± 95F)
Engine rpmKeep to 1,500 rpm.
Blower motor switchMax. (4th position)
Temperature controlMax. cool
Air outlet controlFace
Vehicle doorsAll open
Air inlet door positionRecirculation
8) With about 20 mm (0.8 in.) of dry bulb thermometer (1) inserted
into center duct air outlet and another one set near evaporator
air inlet, read temperature indicated on each thermometer.
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
1. Blower motor main relay
2. Blower motor
3. Blower motor resistor
4. Blower motor switch
5. A / C controller
6. ECM
7. Heater mode control switch
8. Evaporator temperature sensor
9. Refrigerant pressure switch10. Compressor relay
11. Compressor
12. Condenser cooling fan relay
13. Condenser cooling fan
14. Fuse box
15. A / C fuse 25 A
16. Ignition switch
17. Main fuse box
18. Battery main fuse 80 A19. Battery
20. Generator
21. Ignition main fuse 60 A
22. Heater/A/C main fuse 60 A
23. Ignition / meter fuse 20 A
24. Rear defogger fuse 15 A
25. Heater fuse 30 A
26. Compressor thermal switch
(only IWATA production vehicle)
FOR LH VEHICLE
1B-16 AIR CONDITIONING (OPTIONAL)
WIRING CIRCUIT