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
YH4
GRAND
VITARA
AIR CONDITIONING (OPTIONAL) 1B-17
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 switch
FOR RH VEHICLE
10. 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)
YH4
GRAND
VITARA
SYSTEM CIRCUIT
A. To heater fuse
B. To rear defogger fuse
C. To ignition / meter fuse
D. To A / C fuse
E. Only LH vehicle1. Blower motor relay
2. Blower motor
3. Blower motor switch
4. A / C switch
5. Deflloster position switch
6. Deflloster / foot position switch7. Dual pressure (refrigerant
pressure) switch
8. A / C thermistor (evaporator
temperature sensor)
9. Compressor relay
10. Compressor11. Condenser fan motor relay
12. Condenser fan motor
13. A / C controller
14. ECM
15. Compressor thermal switch
(only IWATA production vehicle)
TERMINAL ARRANGEMENT OF A / C CONTROLLER
TERMINAL ARRANGEMENT OF ECM FOR G16, J20 ENGINE
TERMINAL ARRANGEMENT OF ECM FOR H25 ENGINE
H25 engine
E61-27
G16, J20
engines
E61-8
H25 engine
E61-28
G16, J20
engines
E61-17
1919
19H25 engine
E61-5
G16, J20
engines
E61-22
AIR CONDITIONING (OPTIONAL) 1B-19
YH4
GRAND
VITARA
1B-20 AIR CONDITIONING (OPTIONAL)
A / C CONTROLLER VOLTAGE VALUES TABLE
TerminalWireCircuitMeasurement
groundNormal valueCondition
AC1-1B/WController main
power supplyGround to
engine (Fig. B)10 ± 14 voltsIgnition switch ON with engine
stopped
AC1-2B/YController main
groundGround to body
(Fig. A)± 0.4 ± 0 voltEngine running
AC1 4Or
Refrigerant
p
ressure switchGround to
0 ± 1 volt
Refrigerant pressure within 225 kPa
(2.3 kg / cm
2, 32.7 psi) to 2548 kPa
(26 kg / cm
2, 370 psi) with engine
running
AC1-4Orpressure switch
inputengine (Fig. B)
10 ± 14 volts
Refrigerant pressure below
196 kPa (2.0 kg / cm
2, 28 psi) or
above 3140 kPa (32 kg / cm
2, 455 psi)
with engine running
AC1 7G/B
A / C switch input
and / or defroster
Ground to
8 ± 14 volts
Blower fan motor switch and A / C or
defroster position switch (see NOTE)
ON with engine running
AC1-7G/Bposition switch
input (see NOTE)engine (Fig. B)
0 ± 1.5 volts
Blower fan motor switch or A / C or
defroster position switch (see NOTE)
OFF with engine running
AC1 9Gr/W
Signal input from
ECM (A / C ON
Ground to10 ± 14 voltsApprove of A / C ON
AC1-9Gr/W(
permission
signal)engine (Fig. B)0 ± 1 voltA / C ON forbid
AC1-13Y/B
Signal output to
ECM (A / C ON
request signal)Ground to engine
(Fig. B)0 ± 1.5 volts
Blower fan motor switch and A / C or
defroster position switch (see NOTE)
ON with engine running at evaporator
thermistor temperature input more
than approx. 2.5C (less than 2.5 V
(5840 )) and refrigerant pressure
switch is ON
10 ± 14 voltsExcept the above-mentioned with
engine running
AC1-16P
Compressor
magnet clutch
relay outputGround to engine
(Fig. B)0 ± 1 volt
Blower fan motor switch and A / C or
defroster position switch ON with
engine running at evaporator
thermistor temperature input more
than approx. 2.5C (less than 2.5 V
(5840 )), refrigerant pressure
switch ON and signal input from ECM
ON
10 ± 14 voltsExcept the above-mentioned with
engine running
YH4
GRAND
VITARA
AIR CONDITIONING (OPTIONAL) 1B-21
TerminalWireCircuitMeasurement
groundNormal valueCondition
AC2-1L/YSensor groundGround to body
(Fig. A)± 0.4 ± 0 voltEngine running
1.5 volts
(3150 )Evaporator thermistor temperature at
approx. 15C (59F) with engine
running
AC2-2W/B
Evaporator
thermistor
temperature
(evaporator temp.
sensor) input
Ground to engine
(Fig. B)
2.62 volts
(6.311 )
Evaporator thermistor temperature at
approx. 1C (34F) with engine
running
* If the temperature is less than
approx. 1C, in this case
compressor and condenser fan
should be stop (come back at more
than approx. 2.5C (less than
5840 , 2.5 V))
H25
engine
E61-27 /
G16 J20Gr/W
Signal output to
A / C controller
(A / C ON
Ground to engine
(Fig C)
10 ± 14 volts
Required A / C ON (terminal AC-A13)
at engine running with normal
condition (refer to ªINSPECTION OF
ECM AND ITS CIRCUITº in Section
6E)
G16, J20
engines
E61-8
(
permission
signal)(Fig. C)
0 ± 1 volt
Except the above-mentioned with
engine running
In this case compressor should be
stop
H25
engine
E61-28 /
Y/B
Signal input from
A / C controller
Ground to engine
0 ± 1.5 voltsRequire A / C ON
G16, J20
engines
E61-17Y/B(A / C ON request
signal)
g
(Fig. C)
10 ± 14 voltsTurn off the A / C
H25
engine
E61-5 /
G16, J20
engines
E61-22
Y/L
A / C condenser
cooling fan relay
outputGround to engine
(Fig. C)0 ± 1 volt
Blower fan motor switch and A / C or
defroster position switch (see
NOTE) ON with engine running at
evaporator thermistor temperature
input more than approx. 2.5C (less
than 2.5 V (5840 )), refrigerant
pressure switch ON and signal
input from ECM ON
Engine coolant temperature sensor
more than 113C (236F) with
engine running
10 ± 14 voltsExcept the above-mentioned with
engine running
NOTE:
Defroster position switch circuit is equipped with LH vehicle only.