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 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 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 1142 of 1202
N13790
Low Pressure
Service Valve
High Pressure
Service Valve
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-13
1996 TERCEL (RM440U)
3. CHARGE REFRIGERANT INTO REFRIGERANT SYS-
TEM
If there is no leakafter refrigerant leak check, charge the proper
amount of refrigerant intor refrigeration system.
CAUTION:
Never run the engine when charging the system
through the high pressure side.
Do not open the low pressure hand a valve when the
system is being charged with liquid refrigerant.
(a) Open the high pressure hand valve fully.
(b) Charge specified amopunt of refrigerant, then close the
high pressure hand valve.
HINT:
A fully charged system is indicated by the sight flass being free
of any bubbles.
4. SET OFF MANIFOLD GAUGE SET
(a) Close both hand valves of manifold gauge set.
(b) Disconnect the quick disconnect adapters from the ser-
vice valves.
5. INSTALL CAPS TO SERVICE VALVES ON REFRIGER-
ANT LINES
Page 1145 of 1202

AC1HH-04
AC-16
- AIR CONDITIONINGTROUBLESHOOTING
1168 Author: Date:
1996 TERCEL (RM440U)
TROUBLESHOOTING
PROBLEM SYMPTOMS TABLE
Use the table below to help you find the cause of the problem. The numbers indicate the priority of the likely
cause of the problem. Check each part in order. If necessary, replace these parts.
SymptomSuspect AreaSee page
No blower operation
2. Heater main relay
3. Blower motor
4. Blower resistor
5. Blower speed control switchAC-62
AC-55
AC-56
AC-71
No air temperature control1. Inspect engine coolant volume
2. A/C control lever-
AC-72
No compressor operation
1. Refrigerant volume
2. A/C Fuse
3. Magnetic clutch relay
4. Magnetic clutch
5. Compressor
6. Pressure switch
7. Heater main relay
8. A/C switch
9. Blower speed control switch
10.A/C amplifier
11. Thermistor
12.Wiring and wiring connectionsAC-3
-
AC-63
AC-40
AC-36
AC-59
AC-59
AC-62
AC-71
AC-66
AC-57
-
Compressor operates intermittently
1. Refrigerant volume
2. Refrigerant cooling system
3. Pressure switch
4. A/C amplifier
5. Thermistor
6. Wiring and wiring connectionsAC-3
-
AC-59
AC-66
AC-57
-
No condenser fan operation
1. Condenser fan fuse
2. Engine main relay
3. Cooling fan relay No.1
4. Cooling fan relay No.2
5. Cooling fan relay No.3
6. Magnetic clutch relay
7. Condenser fan motor
8. Pressure switch
9. Water temperature switch
10.A/C amplifier-
CO-33
AC-64
AC-64
AC-64
AC-63
AC-65
AC-59
-
AC-66
No cool air comes out
1. Refrigerant volume
2. Drive belt
3. Magnetic clutch
4. Compressor
5. Refrigeration controlAC-3
AC-18
AC-40
AC-36
-
Cool air comes out intermittently
1. Refrigerant Volume
2. Drive belt
3. A/C amplifier
4. Expansion valve
5. Evaporator
6. Thermistor
7. Wiring and wiring connectionAC-3
AC-18
AC-66
AC-54
AC-52
AC-57
-
Cool air comes out only at high engine rpm
1. Refrigerant volume
2. Drive belt
3. Inspect refrigerant linesAC-3
AC-18
-
Page 1146 of 1202
- AIR CONDITIONINGTROUBLESHOOTING
AC-17
1169 Author: Date:
1996 TERCEL (RM440U) Insufficient cooling
1. Refrigerant volume
2. Drive belt
3. Refrigerant cooling system
4. A/C amplifier
5. Refrigerant lines
6. ThermistorAC-3
AC-18
-
AC-66
-
AC-57
No engine idle up when A/C switch on
1. Idle air control (IAC) valve
2. A/C amplifier
3. Wiring and wiring connections-
AC-66
-
No warm air comes out
1. Engine coolant volume
2. A/C control lever adjustment
3. Heater radiator-
AC-73
AC-31
Page 1147 of 1202
CH0086
CorrectWrong
AC1C5-04
Z16157
PS Pump
Idle Pulley
Compressor
Compressor Crankshaft
PulleyCrankshaft
Pulley
I17366
Nippondenso Borroughs AC-18
- AIR CONDITIONINGDRIVE BELT
1170 Author: Date:
1996 TERCEL (RM440U)
DRIVE BELT
ON-VEHICLE INSPECTION
1. INSPECT DRIVE BELT'S INSTALLATION CONDITION
Check that the drive belt fits properly in the ribbed grooves.
2. INSPECT DRIVE BELT TENSION
Using a belt tension gauge, check the drive belt tension.
Belt tension gauge:
Nippondenso BTG-20 (95506-00020) or Borroughs
No. BT-33-73F
Drive belt tension:
New belt 160 ± 25 lbf
Used belt 100 ± 20 lbf
HINT:
ºNew beltº refers to a belt which has been used less than
5 minutes on a running engine.
ºUsed beltº refers to a belt which has been used on a run-
ning engine for 5 minutes or more.
After installing the drive belt, check that it fits properly in
the ribbed grooves.
Page 1161 of 1202
AC1CG-04
AC2884
Hose Clip
Heater Radiator
Pipe
Water Hose
InsulatorLeft Side
of Vehicle
N12242
AC-32
- AIR CONDITIONINGHEATER UNIT
1996 TERCEL (RM440U)
REMOVAL
1. REMOVE COOLING UNIT
(See page AC-27)
2. DRAIN ENGINE COOLANT FROM RADIATOR
HINT:
It is not necessary to drain out all the coolant.
3. DISCONNECT WATER HOSES FROM HEATER RA-
DIATOR PIPES
HINT:
Push the water hose onto the heater radiator pipe as far
as the ridge on the pipe.
Install the hose clip in a position, as shown in the illustra-
tion.
4. REMOVE PIPE GROMMETS
5. REMOVE INSTRUMENT PANEL SAFETY PAD AND
REINFORCEMENT (See page BO-48)
6. REMOVE HEATER UNIT
Remove the 2 nuts and the heater unit.
7. REMOVE HEATER RADIATOR
(a) Remove the screw and clamp.
(b) Pull out the heater radiator.