TOYOTA TERCEL 1996 Service Repair Manual
Page 1131 of 1202
AC-2
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
1154 Author: Date:
1996 TERCEL (RM440U)
9. SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
The TERCEL is equipped with as SRS (Supplemental Restraint
System) such as the driver and passenger airbag. Failure to
carry out service operations the correct sequence could cause
the SRS to unexpectedly deployed during servicing, possibly
leading to a serious accident. Further, if a mistake is mode in
serving the SRS, it is possible the SRS may fail to operate when
required. Before servicing (including removal or installation of
parts, inspection or replacement), be sure to read the following
item carefully, then follow the correct procedure described in re-
pair manual.
Page 1132 of 1202
AC2WA-02
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-3
1996 TERCEL (RM440U)
ON-VEHICLE INSPECTION
1. INSPECT REFRIGERANT VOLUME
Observe the sight glass on the liquid tube.
Test conditions:
Running engine at 1,500 rpm
Blower speed control switch at ºHIº position
A/C switch ON
Temperature control set at ºMAX COOLº
Fully open the doors
ItemSymptomAmount of refrigerantRemedy
1Bubbles present in sight glassInsufficient*
(1) Check for gas leakage with gas leak de-
tector and repair if necessary
(2) Add refrigerant until bubbles disappear
2No bubbles present in sight glassNone, sufficient or too muchRefer item 3 and 4
3No temperature difference between com-
pressor inlet and outletEmpty or nearly empty
(1) Check for gas leakage with gas leak de-
tector and repair if necessary
(2) Add refrigerant until bubbles disappear
4Temperature between compressor inlet and
outlet is noticeably differentCorrect or too muchRefer to item 5 and 6
5Immediately after air conditioning is turned
off, refrigerant in sigh glass stays clearToo much
(1) Discharge refrigerant
(2) Evacuate air and charge proper amount
of purified refrigerant
6When air conditioning is turned off, refriger-
ant foams and then stays clearCorrect-
*: Bubbles in the sight glass with ambient temperatures higher than usual can be considered normal if cooling
is sufficient.
Page 1133 of 1202
I01386
AC-4
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
1996 TERCEL (RM440U)
2. INSPECT REFRIGERANT PRESSURE WITH MAN-
IFOLD GAUGE SET
This is a method in which the trouble is located by using a man-
ifold gauge set. Read the manifold gauge pressure when these
conditions are established.
Test conditions:
Temperature at the air inlet with the switch set
at RECURC is 30 - 35 °C (86 - 95 °F).
Engine running at 1,500 rpm.
Blower speed control switch set at high.
Temperature control set at max. cool.
HINT:
It should be noted that the gauge indications may vary slightly
due to ambient temperature conditions.
(1) Normally functioning refrigeration system.
Gauge reading:
Low pressure side:
0.15 - 0.25 MPa (1.5 - 2.5 kgf/cm
2)
High pressure side:
1.37 - 1.57 MPa (14 - 16 kgf/cm
2)
Page 1134 of 1202
I01387
Condition : Periodically cools and then fails to cool
I01388
Condition: Insufficient cooling
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-5
1996 TERCEL (RM440U)
(2) Moisture present in refrigeration system.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
During operation, pressure on low
pressure side sometimes become
a vacuum and sometime normal
Moisture entered in refrigeration
system freezes at expansion valve
orifice and temporarily stops cycle,
but normal state is restored after a
time when the ice melts Drier in oversaturated state
Moisture in refrigeration system
freezes at expansion valve orifice
and blocks circulation of refriger-
ant(1) Replace condenser
(2) Remove moisture in cycle
through repeatedly evacuating air
(3) Charge proper amount of new
refrigerant
(3) Insufficient cooling
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure low on both low and
high pressure sides
Bubbles seen in sight glass con-
tinuously
Insufficient cooling performance
Gas leakage at some place in re-
frigeration system Insufficient refrigerant in system
Refrigerant leaking
(1) Check for gas leakage with gas
leak detector and repair if neces-
sary
(2) Charge Proper amount of re-
frigerant
(3) If indicated pressure value is
near 0 when connected to gauge,
create the vacuum after inspecting
and repairing the location of the
leak
Page 1135 of 1202
I01389
Condition: Insufficient cooling
I01449
Condition: Does not cool (Cools from time to time in some cases) AC-6
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
1996 TERCEL (RM440U)
(4) Poor circulation of refrigerant
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure low in both low and
high pressure sides
Frost on tube from receiver to
unit
Refrigerant flow obstructed by dirt
in receiverReceiver cloggedReplace receiver
(5) Refrigerant does not circulate
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Vacuum indicated on low pres-
sure side, very low pressure indi-
cated on high pressure side
Frost or dew seen on piping be-
fore and after receiver/ drier or ex-
pansion valve Refrigerant flow obstructed by
moisture or dirt in refrigeration sys-
tem
Refrigerant flow obstructed by
gas leakage from expansion valve
Refrigerant does not circulate
(1) Check expansion valve
(2) Clean out dirt in expansion
valve by blowing with air
If not able to remove dirt, replace
expansion valve
(3) Replace receiver
(4) Evacuate air and charge new
refrigerant to proper amount
(5) For gas leakage from expan-
sion valve, replace expansion
valve
Page 1136 of 1202
I01390
Condition: Insufficient cooling
I01392
Condition: Insufficient cooling
NOTE : These gauge indica-
tions are shown when the
refrigeration system has
been opened and the refrig-
erant charged without vacu-
um purging.
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-7
1996 TERCEL (RM440U)
(6) Refrigerant overcharged or insufficient cooling of
condenser
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
No air bubbles seen through the
sight glass even when the engine
rpm is lowered Unable to develop sufficient per-
formance due to excessive refrig-
erant in system
Insufficient cooling of condenser Excessive refrigerant in
cycle " refrigerant overcharged
Condenser cooling "condenser
fins clogged of condenser fan
faulty.(1) Clean condenser
(2) If (1) is normal, check amount
of refrigerant
Charge proper amount or refriger-
ant
(7) Air present in refrigeration system
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
The low pressure piping hot to
the touch
Bubbles seen in sight glass
Air entered in refrigeration system
AIr present in refrigeration sys-
tem
Insufficient vacuum purging
(1) Check compressor oil to see if
it is dirty or insufficient
(2) Evacuate air and charge new
refrigerant
Page 1137 of 1202
I01450
Condition: Insufficient cooling
I01393
Condition : Does not cool AC-8
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
1996 TERCEL (RM440U)
(8) Expansion valve improperly
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
Frost or large amount of dew on
piping on low pressure side
Trouble in expansion valve or heat
sensing tube not installed correctly
Excessive refrigerant in low
pressure piping
Expansion valve opened too
wide
Check expansion valve
Replace if defective
(9) Defective compression compressor
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on low and
high pressure sides
Pressure too low on high pres-
sure side
Internal leak in compressor
Compression defective
Valve leaking or broken sliding
parts
Repair or replace compressor
Page 1138 of 1202
N14519
Drain Hose
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-9
1996 TERCEL (RM440U)
3. INSPECT IDLE-UP SPEED
(a) Warm up engine.
(b) Inspect idle-up speed when the these conditions are es-
tablished.
Test conditions:
Blower speed control switch HI
Electrical lood OFF
A/C switch ON
Put gear shift in neutral
Standard idle-up speed: 800 - 900 rpm
If idle speed is not as specified, check the IAC valve and air in-
take system.
4. INSPECT FOR LEAKAGE OF REFRIGERANT
(a) Perform in these conditions:
Stop engine.
Secure good ventilation (If the gas leak detector
may not react to volatile gases which are not refrig-
erant, such as evaporated gasoline and exhaust
gas.)
Repeat the test 2 or 3 times.
Make sure that there is some refrigerant remaining
in the refrigeration system.
When compressor is OFF: approx. 392 - 588 kPa
(4 - 6 kgf/ cm
2, 57 - 85 psi)
(b) Bring the gas leak detector close to the drain hose before
performing the test.
HINT:
After the blower motor has stopped, leave the cooling unit
for more than 15 minutes.
Expose the gas leak detector sensor under the drain
hose.
When bring the gas leak detector close to the drain hose,
make sure that the gas leak detector does not react to the
volatile gases.
If such reaction is unavoidable, the vehicle must be lifted up.
(c) If gas leak is not detected on the drain hose, remove the
power transistor from the cooling unit. Then insert the gas
leak detector sensor into the unit and perform the test.
(d) Disconnect the connector and leave the pressure switch
for approx. 20 minutes. Then bring the gas leak detector
close to the pressure switch and perform the test.
(e) Bring the gas leak detector close to the refrigerant lines
and perform the test.
Page 1139 of 1202
N17949
N14517
Gas Leak
Detector
Pressure
Switch AC-10
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
1996 TERCEL (RM440U)
(f) Disconnect the connector and leave the pressure switch
for approximately 20 minutes. Then bring the gas leak de-
tector close to the pressure switch and perform the test.
(g) Bring the gas leak detector close to the refrigerant lines
and perform the test.
HINT:
Make sure that there is no dirt on joints.
Page 1140 of 1202
AC1DT-01
N13795
Quick Disconnect
Adapter
Charging
Service ValveHose
N13794
Vacuum Pump
Vacuum Pump Adapter
N13791
Low Pressure
Service Valve
Vacuum Pump Adapter High Pressure
Service ValveManifold
Gauge
Set
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-1 1
1996 TERCEL (RM440U)
EVACUATING
1. CONNECT QUICK DISCONNECT ADAPTER TO
CHARGING HOSES
2. REMOVE CAPS FROM SERVICE VALVES ON RE-
FRIGERANT LINES
3. SET ON MANIFOLD GAUGE SET
(a) Close both hand valves of manifold gauge set.
(b) Connect the quick disconnect adapters to the service
valves.
4. EVACUATE AIR FROM REFRIGERATION SYSTEM
(a) Connect the vacuum pump adapter to the vacuum pump.
(b) Connect the center hose of the manifold gauge set to the
vacuum pump adapter.
(c) Open both the high and low hand valves and run the vacu-
um pump.
(d) After 10 minutes or more, check that the low pressure
gauge indicates 750 mmHg (30 in. Hg) or more.
HINT:
If the reading is 750 mmHg (30 in. Hg) or more, close both hand
valves of manifold gauge set and stop the vacuum pump.
Check the system for leaks and repair if necessary.
(e) Close both the high and low hand valves and stop the vac-
uum pump.
(f) Leave the system in this condition for 5 minutes or more
and check that there is no gauge indicator.