Page 78 of 687
Downloaded from www.Manualslib.com manuals search engine AIR CONDITIONING (OPTIONAL) 1B-17
A/C System Inspection of ECM and ITS Cir-
cuits
ECM and its circuits can be checked at ECM wiring couplers by
measuring voltage.
Voltage Check
1) Remove ECM from vehicle by referring to “Engine Control
Module” in Section 6E.
2) Connect ECM couplers (1) to ECM (2).
3) Check voltage at each terminal of couplers connected.CAUTION:
ECM cannot be checked by itself. It is strictly prohibited
to connect voltmeter or ohmmeter to ECM with couplers
disconnected from ECM.
NOTE:
Because each terminal voltage is affected by the battery
voltage, confirm that the battery voltage is 11 V or more
when ignition switch is ON.
[A] : Fig. A
[B] : Fig. B
3. E19-3
Page 79 of 687
Downloaded from www.Manualslib.com manuals search engine 1B-18 AIR CONDITIONING (OPTIONAL)
Terminal arrangement of ECM coupler (Viewed from harness side)
1. Blower fan motor 8. Compressor [A]: To “A/C” fuse (25A) in main fuse box
2. Dual pressure switch 9. Thermal switch [B]: To “HEATER” fuse (20A) in circuit fuse box
3. A/C switch 10. Main relay [C]: To “FI” fuse (15A) in main fuse box
4. A/C evaporator thermistor 11. Engine earth [D]: 4WD model
5. ECT sensor 12. Blower fan motor switch [E]: 2WD model
6. Condenser cooling fan motor relay 13. 4WD controller
7. Condenser cooling fan motor 14. ECM
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ECM VOLTAGE VALUES TABLE FOR RELATION OF A/C CONTROL
Terminal Wire CircuitMeasurement
groundNormal value Condition
E18-1 PCompressor
magnet clutch
outputGround to
engine (Fig B)10 – 14 voltBlower fan motor switch and A/C
switch ON with engine running
0 – 1 voltsExcept the above-mentioned condi-
tion with engine running
E18-5 Bl/BMain power sup-
ply for ECMGround to
engine (Fig B)10 – 14 voltsIgnition switch ON with engine
stopped
E18-6 Bl/BMain power sup-
ply for ECMGround to
engine (Fig B)10 – 14 voltsIgnition switch ON with engine
stopped
E18-10 Bl Main relay driveGround to
engine (Fig B)0.5 – 1.2 voltIgnition switch ON with engine
stopped
0 volts Ignition switch OFF
E18-16 G/W A/C switch inputGround to
engine (Fig B)12 – 15 voltsBlower fan motor switch or A/C switch
OFF with engine running
0 – 1 voltBlower fan motor switch and A/C
switch ON with engine running
12 – 15 voltsWithin several seconds after operate
transfer lever between 2WD and 4WD
with above condition
E18-18 P/BCompressor
cooling fan relay
outputGround to
engine (Fig B)0 – 1 voltBlower fan motor switch and A/C
switch ON or engine coolant tempera-
ture at more than 110 °C (230 °F) with
engine running.
12 – 15 voltsExcept the above-mentioned condi-
tion with engine running
E18-20 B/BlSensor ground
for A/C evapora-
torGround to
body (Fig A)–0.5 – 0 volt Engine running
E18-24 Bl/YBlower fan
speed inputGround to
engine (Fig B)0 – 1 voltBlower fan motor switch 2nd or 3rd
with engine running
4 – 7 voltsBlower fan motor switch 1st with
engine running
12 – 15 voltsBlower fan motor switch and A/C
switch OFF with engine running
E19-1 BMain ground for
ECMGround to
engine (Fig A)–0.5 – 1 volt Engine running
E19-2 B/RECM ground for
power circuitGround to
engine (Fig A)–0.5 – 1 volt Engine running
E19-3 B/RECM ground for
power circuitGround to
engine (Fig A)–0.5 – 1 volt Engine running
E19-10 B/BlSensor ground
for ECT sensorGround to
body (Fig A)–0.5 – 1 volt Engine running
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E19-14 G/BECT sensor
inputGround to
engine (Fig B)0.73 – 0.83 volts
(315 – 355 Ω)Engine coolant temperature at
approximately 80 °C (176 °F) with
engine running
0.35 – 0.45 volts
(145 – 165 Ω)Engine coolant temperature at
approximately 110 °C (230 °F) with
engine running
*If the temperature is more than
113 °C (235 °F), compressor should
be stop (come back at less than
111 °C (232 °F)
E19-27 W/RA/C evaporator
thermistor tem-
perature inputGround to
engine (Fig B)2.0 – 2.3 volts
(1800 – 2200 Ω)Evaporator thermistor temperature at
approximately 25 °C (77 °F) with
engine running
3.5 – 3.6 volts
(6300 – 7000 Ω)Evaporator thermistor temperature at
approximately 0 °C (32 °F) with
engine running
*If the temperature is less than
approximately 2.5 °C (36.5 °F), com-
pressor cooling fan should be stop
(come back at less than approxi-
mately 4 °C (39.2 °F) Terminal Wire CircuitMeasurement
groundNormal value Condition
Page 82 of 687

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Refrigerant Recovery, Evacuating and Charging
Operation Procedure for Refrigerant Charging
WARNING:
Your eyes should not be exposed to refrigerant (liquid).
Any liquid HFC-134a (R-134a) escaping by accident shows a temperature as low as approximately
–6 °C (21 °F) below freezing point. Should liquid HFC-134a (R-134a) get into your eyes, it may cause
a serious injury. To protect your eyes against such accident, it is necessary to always wear gog-
gles. Should it occur that HFC-134a (R-134a) strikes your eyes(s), consult a doctor immediately.
– Do not use your hand to rub the affected eye(s). Instead, use quantities of fresh cold water to
splash it over the affected area to gradually raise temperature of such area above freezing point.
– Obtain proper treatment as soon as possible from a doctor or eye specialist.
Should the HFC-134a (R-134a) liquid come into contact with your skin, the affected area should be
treated in the same manner as when skin is frostbitten or frozen.
Refrigerant must not be handled near where welding or steam cleaning is performed.
Refrigerant should be kept at a cold and dark place. It should never be stored where a high temper-
ature is anticipated, e.g. where exposed to direct sun light, close to fire or inside vehicle (including
trunk room).
Avoid breathing fumes produced when HFC-134a (R-134a) is burned. Such fumes may be hazardous
to health.
Replenish compressor oil
Start evacuating
Inspect and repair connections
Charge 550 50 g of
refrigerant in gas form Stop evacuating 15 minutes (–760 mmHg)
Wait 10 mintues
If gauge shows
abnormal conditions Check system for
pressure tightness
Check A/C system
With refrigerant
Check system for refrigerant
leaks and refrigerant
charging quantity
Performance test
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Recovery
REFRIGERANT RECOVERY
When evacuating A/C system, always recover refrigerant by using
equipment (1) for refrigerant recovery and recycling. Discharging
refrigerant HFC-134a (R-134a) into atmosphere would cause
adverse effect to environments.
Replenishing Compressor Oil
It is necessary to replenishing specified amount of compressor oil
to compressor (1) from compressor suction side hole (2) before
evacuating and charging refrigerant.
Compressor oil
99000-99088-00D0
WHEN CHARGING REFRIGERANT ONLY
When charging refrigerant without replacing any component part,
replenish the same amount of measured oil when recover refrig-
erant (if not measure, replenish 30 cc oil).NOTE:
After recover refrigerant from system, the amount of
removed compressor oil must be measured for replen-
ishing compressor oil.
When handling recovery and recycling equipment, be
sure to follow the instruction manual for the equip-
ment.
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WHEN REPLACING COMPRESSOR
Compressor oil is sealed in each new compressor by the amount
required for A/C system. Therefore, when using a new compres-
sor for replacement, drain oil from new compressor by the amount
calculated as follows.
“C” = “A” – “B”
“C” : Amount of oil to be drained
“A” : Amount of oil sealed in a new compressor
“B” : Amount of oil remaining in removed compressor
WHEN REPLACING OTHER PART
Replenish the following amount of oil to compressor.
Amount of compressor oil to be replenished
Evacuating
Evacuating procedure
Whenever opened (exposed to atmospheric air), A/C system
must be evacuated by using a vacuum pump.
1. New compressor
2. Removed compressor
Replaced part Amount of compressor oil to be
replenished
Evaporator
30 cm
3 (30 cc, 1.83 cu-in)
Condenser
30 cm
3 (30 cc, 1.83 cu-in)
Receiver / dryer
20 cm
3 (20 cc, 1.22 cu-in)
Hoses
10 cm
3 (10 cc, 0.61 cu-in) each
Pipes
10 cm
3 (10 cc, 0.61 cu-in) each
NOTE:
Do not evacuate before recovering refrigerant and replen-
ishing compressor oil.
Page 85 of 687

Downloaded from www.Manualslib.com manuals search engine 1B-24 AIR CONDITIONING (OPTIONAL)
1) Connect high charging hose (1) and low charging hose (2) of
manifold gauge set (3) respectively as follows:
High charging hose (1) → High pressure charging valve (4)
on discharge hose
Low charging hose (2) → Low pressure charging valve (5) on
suction hose
2) Attach center charging hose (6) of manifold gauge set (3) to
vacuum pump (7).
3) Operate vacuum pump (7), and then open discharge side
valve (Hi) (8) of manifold gauge set (3).
If there is no blockage in the system, there will be an indica-
tion on high pressure gauge (9).
In this case, open the other side valve (Lo) (10) of the set
and repair the system.
4) Approximately 10 minutes later, low pressure gauge (11)
should show a vacuum lower than –760 mmHg providing no
leakage exists.
5) Evacuation should be carried out for a total of at least 15
minutes.
6) Continue evacuation until low pressure gauge (9) indicates a
vacuum less than –760 mmHg, and then close both valves
(8), (10).
7) Stop vacuum pump (7). Disconnect center charging hose (6)
from pump inlet. Now, the system is ready for charging refrig-
erant. NOTE:
If the system does not show a vacuum below –760
mmHg, close both valves, stop vacuum pump and
watch movement of low pressure gauge.
Increase in the gauge reading suggests existence of
leakage. In this case, repair the system before continu-
ing its evacuation.
If the gauge shows a stable reading (suggesting no
leakage), continue evacuation.