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
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.
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.
YH4
GRAND
VITARA
7B1-4 AUTOMATIC TRANSMISSION (4 A / T)
ItemSpecifications
Torque
conver-
terType
Stall torque ratio3-element, 1-step, 2-phase type (with TCC (lock-up)
mechanism)
2.4 (G16 engine) 2.0 (J20 engine) 1.9 (H25 engine)
Oil
pumpType
Drive systemTrochoid type oil pump
Engine driven
TypeForward 4-step, reverse 1-step planetary gear type
Shift position
ªPº range Gear in neutral, output shaft fixed,engine start
ªRº range Reverse
ªNº range Gear in neutral, engine start
ªDº range Forward 1st 2nd 3rd 4th (O / D)
(O / D ON) automatic gear change
ªDº range Forward 1st 2nd 3rd
(O / D OFF) automatic gear change
ª2º range (Normal mode) Forward 1st 2nd 3rd automatic gear
change
(Power mode) Forward 2nd 3rd automatic gear
change and fixed at 2nd gear
ªLº range Forward 1st 2nd 3rd reduction, and fixed at 1st gear
GearEngine typeG16 engineJ20 / H25 engines
change
device1st (low gear)2.8262.826device2nd (second gear)1.4931.493
Gear3rd (top gear)1.0001.000Gear
ratio4th (overdrive
4th gear)0.7300.689
Reverse (reverse
Reverse gear)2.7032.703
Control elements
Wet type multi-disc clutch 3 sets. . . . . . . . . .
Wet type multi-disc brake 4 sets. . . . . . . . . .
One-way clutch 3 sets. . . . . . . . . . . . . . . . . . .
TransferHi: 1.000 Lo: 1.816 (4WD model only)
Final gear reduction
ratio (Differential)5.125 (G16 engine) 4.875 (J20 / H25 engines)
Lubrica-
tionLubrication systemForce feed system by oil pump
CoolingCooling systemRadiator assisted cooling (water-cooled)
Fluid usedAn equivalent of DEXRONIII
YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-31
Brake pedal Released Depressed
Voltage 0 VBattery
voltage
DIAGNOSTIC FLOW TABLE A-1 (NO TCC LOCK-UP OCCURS)
SYSTEM DESCRIPTION
PCM turns TCC solenoid OFF under any of the following conditions.
Brake pedal switch: ON
4WD LOW switch: ON
Cruise control module: TCC OFF command signal is output (if equipped).
ECT: ECT < 30C (86F)
TROUBLESHOOTING
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 person, a driver and tester, on a level road.
STEPACTIONYESNO
1Was ªAUTOMATIC TRANSMISSION
DIAGNOSTIC FLOW TABLEº performed?Go to Step 2.Go to ªAUTOMATIC
TRANSMISSION
DIAGNOSTIC FLOW
TABLEº.
2ECT check:
(1) Warm up engine to normal operating
temperature.
(2) Check ECT using scan tool.
Is ECT more than 30C (86F)?Go to Step 3.Faulty ECT sensor, its
circuit or engine cooling
system.
If OK, substitute a known-
good PCM and recheck.
3Perform running test under the following
conditions and check voltage between
C51-1-8 (G16 / J20 engines) or C51-1-2 (H25
engine) terminal of PCM coupler and ground.
Normal mode in ªDº range.
Transfer ª2Hº position.
Cruise control is not operated (if equipped).
Brake pedal released.
Drive vehicle with TCC ON condition
referring to ªTCC lock-up diagramº in
this section.
Is it battery voltage?Faulty TCC solenoid
valve, its circuit or
transmission.Go to Step 4.
4Is vehicle equipped with H25 engine?Go to Step 5.Go to Step 6.
5Brake switch signal inspection:
(1) With ignition switch ON, check voltage
between E61-31 terminal of PCM coupler
terminal and ground.
Is the result as specified?Go to Step 6.Faulty brake pedal switch
or its circuit.
If OK, substitute a known-
good PCM and recheck.
YH4
GRAND
VITARA
AUTOMATIC TRANSMISSION (4 A / T) 7B1-33
O / D cut
switchOFF ON
VoltageBattery
voltage0 V
DIAGNOSTIC FLOW TABLE A-2 (NO GEAR SHIFT TO O / D)
SYSTEM DESCRIPTION
PCM does not shift to O / D gear under any of the following conditions.
O / D cut switch: ON
4WD LOW switch: ON
Cruise control module: O / D OFF command signal is output (if equipped).
ECT: ECT < 30C (86F)
TROUBLESHOOTING
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 person, a driver and tester, on a level road.
STEPACTIONYESNO
1Was ªAUTOMATIC TRANSMISSION
DIAGNOSTIC FLOW TABLEº performed?Go to Step 2.Go to ªAUTOMATIC
TRANSMISSION
DIAGNOSTIC FLOW
TABLEº.
2ECT check:
(1) Warm up engine to normal operating
temperature.
(2) Check ECT using scan tool.
Is ECT more than 30C (86F)?Go to Step 3.Faulty ECT sensor,
its circuit or engine
cooling system.
If OK, substitute a known-
good PCM and recheck.
3Perform running test under the following
conditions and check voltage between
C51-1-2 (G16 / J20 engines) or C51-1-6 (H25
engine) terminal of PCM coupler and ground,
C51-1-1 terminal of PCM coupler and ground.
O / D cut switch OFF (ªO / D OFFº lamp OFF).
Normal mode in ªDº range.
Transfer ª2Hº position.
Cruise control is not operated (if equipped).
Drive vehicle with 4th gear condition
referring to ªGear shift diagramº in this
section.
Is each voltage about 0 V?Faulty shift solenoid
valve, its circuit or
transmission.ªGº wire or ªG / Rº wire
shorted to power circuit.
If OK, go to Step 4.
4O / D cut switch signal inspection:
(1) With ignition switch ON, check voltage
between E61-33 (G16 / J20 engines) or
E61-14 (H25 engine) terminal of PCM
coupler and ground.
Is the result as specified?Go to Step 5.Faulty O / D cut switch or
its circuit.
If OK, substitute a known-
good PCM and recheck.