15 HEATER
86U15X-218
86U15X-219
86U15X-220
r.". 1
T 1 11 1.11 -4
y -L -v* X /
1
C I y
1 A +
Voltmeter
2. Connect a resistance (at least 1 kfi) between Q ter-
minal and T terminal.
Set temperature control lever to center position be-
tween MAX HOT and MAX COLD. Connect a jum-
per wire between V terminal and S terminal, and
check the voltage between each terminal using a
voltmeter.
Terminals Voltage
Q - L Approx. 12V
T - L Less than 1V
3. Connect a resistance (at least 1 kfi) between Q ter-
minal and T terminal.
Set temperature control lever to MAX HOT, and
check that Q terminal voltage is higher than termi-
nal t voltage.
4. Connect a resistance (at least 1 M2) between Q ter-
minal and terminal t.
Set temperature control lever to MAX COLD, and
check that T terminal voltage is higher than Q ter-
minal voltage.
Checking A/C Switch and ECO Switch Circuit
1. Turn the A/C switch off.
Connect a jumper wire between terminal c and ter-
minal L.
Connect a resistance (at least 1 kQ) between each
terminals, and check the voltage between these
terminals.
Terminals Voltage
d-g OV
d - f OV
d - h OV
86U15X-221
15-126
16 OUTLINE
OUTLINE
AIR DISTRIBUTION
Vehicles with air conditioner
Side ventilator outlet
1
Center ventilator outlet
- Defroster = outlet
FRESH air inlet
REC air inlet
Side . ventilator < outlet
Floor outlet
Temperature control lever
*
REC-FRESH air selector lever
•QDOODDDaaacziciz) ^^^ ° cQ^
^J 'i, *
OFF
1 7 3 4
Mode control lever
Mode control switch
A/C
DECO
Blower switch
REC-FRESH air selector switch
«?/ ^ W ^
izzi • izn •
C^) A/C - ECDN
• CUD
<=i ac3 a ua • • Jf OFF 12 3 4. SJ
Temperature control lever Blower switch
69G16X002
16-2
OUTLINE 16
The air distribution is shown in the figure.
"I.The door (D1) is used to select either fresh air from outside or recirculated air. Setting the
RECIRC/FRESH control lever (switch) to the FRESH position will allow outside air to come inside.
Setting the RECIRC/FRESH control lever (switch) to the RECIRC position will allow inside air to recir-
culate.
2. Outlet airflow is controlled by doors D3, D4, D5.
Moving (pushing) the mode control lever (switch) opens and shuts the doors (D3, D4, D5) and cre-
ates the air passage according to the lever position.
1) Setting the lever to the VENT position (push the VENT switch) creates the air passage to the venti-
lator outlets, and air comes into the passenger compartment from the ventilator outlets.
2) Setting the lever to the BI-LEVEL position (push the BI-LEVEL switch) creates the air passage
to the ventilator outlets and to the floor outlets.
3) Setting the lever to the HEAT position (push the HEAT switch) creates the air passage to the floor
outlets.
(A little air comes from the defroster outlets.)
4) Setting the lever to the DEF/HEAT position (push the DEF/HEAT switch) creates the air passage
to the floor outlets and to the defroster outlets.
5) Setting the lever to the DEF position (push the DEF switch) creates the air passage to the defroster
outlets.
3. The cooling or heating temperature is controlled by doors D2.
76G16X-002
16-3
OUTLINE 16
TROUBLESHOOTING GUIDE
Problem Probable cause Remedy Reference page
No blower
1. Main fuse (30
A) is
open Replace
operation
2 Malfunction
of
the blower motor Replace 3. Faulty resistor Replace 4. Malfunction
of
the blower switch Replace 5. Open
or
loose connection
in an
electrical circuit Repair 16—6,
7
Insufficient
1. Obstruction
in
the inlet
of
the blower unit Remove the obstruction 16-26
air
2. Clogged evaporator Clean the evaporator
with compressed
air
16-27 3. Frosted evaporator Check the thermostat 16-30 4. Air leakage Check for leakage
at
16-26 both sides
of
the cool-
ing unit
Compressor
1. Malfunction
of
the A/C relay Check operation 16—30
does not run,
2. Malfunction
of
the thermostat Check operation 16—30
or runs
3. Malfunction
of
the refrigerant-pressure switch Check operation 16—31
insufficiently
4.
Air
conditioner fuse (15
A)
failure Replace 5. Compressor drive belt
is
loose Readjust 16—23
6. Internal problem
of
the compressor Repair
or
replace
the
16—13
compressor 7. Battery voltage too low Recharge the battery 8. Layer short
in
the magnet coil Replace 9. Clutch face dirty with
oil
Clean
or
replace the 16-13
clutch 10. Excessive gap between the drive plate and
the
Adjust the gap 16-13
pulley
11. Open circuit
in
the magnet coil Replace 16—13
12 Open circuit Repair 16-6,
7
Refrigeration
Normal pressures are:
pressure is
High pressure
1472—1765 kPa
abnormal (15—18 kg/cm2, 214—255 psi)
Low pressure
197—294 kPa
(2—3 kg/cm2, 29—42 psi)
when: ambient temperature 35°C (95°F)
engine speed 1,500
rpm
Low pressure
1. Internal malfunction
of
the compressor Repair
or
replace the 16-13
is too high
compressor
2. Faulty contact
of
the sensing bulb
of
the expan-Repair 16-26
sion valve 3. Faulty insulation
of
the sensing bulb
of
the expan-Repair 16—26
sion valve
4. Expansion valve open too much Replace 16—26
Low pressure
1. Insufficient refrigerant Charge with refrigerant 16-8
is too low
2. Receiver-drier
is
clogged Replace 16-25
3. Expansion valve
is
clogged Replace 16-26
4. Faulty thermostat Check operation 16-30 5. Frosted piping Clean
or
replace the 16—29
piping
High pres-
1. Poor cooling
of
condenser Check and clean 16-24
sure is too
2. Loose cooling fan drive belt Readjust 16—23
high
3. Too much refrigerant Discharge the excess 16-8
refrigerant 4.
Air in
the system Evacuate and charge 16-8
the system
High pres-
1. Insufficient refrigerant Charge with refrigerant 16-8
sure is too
2. Internal malfunction
of
the compressor Repair
or
replace the 16-13
low
compressor
76G16X-004
16—5
16 OUTLINE
Sight glass
REFRIGERATION SYSTEM
Checking the Refrigerant Charge
1. Run the engine at idle.
2. Operate the air conditioner at maximum cooling
for a few minutes.
3. Check the amount of refrigerant by observing the
sight glass on the receiver-drier. (Refer to follow-
ing table.)
76G16X-005
Item Symptom Amount of refrigerant Remedy
1 Bubbles present
in
sight glass. Insufficient refrigerant. Check
for
leakage with
a gas
leak tester.
2 No bubbles present
in
sight
glass.
No
(or
insufficient) refrigerant. Refer
to
items
3
and
4.
3 No temperature difference
be-
tween compressor inlet and outlet.
System
is
empty
or
nearly empty. Evacuate and charge the sys-tem. Then check
for
leakage with
a
gas leak tester.
4 Temperature between compres-sor inlet and outlet
is
noticeably different.
Proper amount
of (or
too much) refrigerant. Refer
to
items
5
and
6.
5 Immediately after the
air
condi-tioner
is
turned off, refrigerant
in
sight glass stays clear.
Too much refrigerant. Discharge the excess refrigerant
(to the specified amount).
6 When the
air
conditioner
is
turned off, refrigerant foams and
then stays clear.
Proper amount
of
refrigerant. Refrigerant amount
is
normal.
Installation of the Manifold Gauge Set
Note:
Fittings for attaching the manifold gauge set
are on the high and low pressure pipes.
1. Close both hand valves of the manifold gauge set.
2. Install the charging hoses in the gauge set to the
fittings.
Connect the low-pressure hose to the low-pressure
gauge fitting and the high-pressure hose to the
high-pressure gauge fitting.
Tighten the hose nuts by hand.
69G16X-017
16-8
16 OUTLINE
Safety Precautions
1. The R-12 liquid refrigerant is highly volatile. A drop
of it on the skin of your hand could result in local-
ized frostbite. When handling the refrigerant, be
sure to wear gloves.
2. If the refrigerant splashes into your eyes, wash
them with clean water immediately. It is standard
practice to wear goggles or glasses to protect your
eyes, and gloves to protect your hands.
3. The R-12 container is a highly pressurized vessel.
Never leave it in a hot place, and check to be sure
that the temperature where it is stored is below
52°C (126°F).
4. A halide leak detector is often used to check the
system for refrigerant leakage. Remember that
R-12, upon coming into contact with flame (this de-
tector burns like propane to produce a small flame),
produces phosgene, a toxic gas.
69G16X020
V/^V
Connection
LZl
jvmi
Refrigerant Container Service Valve
1. Before connecting the valve to the refrigerant con-
tainer, turn the handle fully counterclockwise.
2. Turn the disc counterclockwise until it reaches its
highest position.
3. Connect the center hose to the valve fitting. Turn
the disc fully clockwise by hand.
4. Turn the handle clockwise to make a hole in the
sealed tap.
5. Turn the handle fully counterclockwise to fill the
center hose with air. Do not open the high- and
low-pressure manual valves.
6. Loosen the center hose nut connected to the cen-
ter fitting of the manifold gauge.
Allow air to escape for a few seconds, then tight-
en the nut.
69G16X-021
16-10
16 OUTLINE
Thermometer (Dry)
Thermometer
(Dry & Wet)
76G16X-633
69G16X-024
DETERMINING THE RELATIVE HUMI-DITY: Read the temperatures of the dry- and v^et-bulb thermometers at the air inlet (evapo-rator inlet). Then bring them into mutual relation on the chart and determine the intersection, which is the relative humidity^ For exampie, if the dry-bulb temperature^ is 90° F. and the wet-bulb temper- ^ ature is 78° F, the relative humidity is ^ 60%.
DRV BUL8 TEMPERATURE
Performance Test
After finishing repairs, be sure to conduct a perfor-
mance test of the air conditioning system as follows.
Procedure
1. Connect the manifold gauge set. (Refer to page
16-8)
2. Run the engine and keep the engine speed at
1750 rpm.
3. Operate the air conditioner at MAX COOLING.
4. Open all windows and doors.
5. Insert a dry-bulb thermometer in the center of the
ventilator outlet.
6. Place a dry and wet thermometer close to the in-
let of the blower inlet.
7. The high pressure should be within 1374—1569
kPa (14.0—16.0 kg/cm2, 200—227 psi).
Note:
If the pressure is too high, pour water on the
condenser; if it is too low, cover the front sur-
face of the condenser.
8. The dry-bulb thermometer at the inlet should be
within 25—35°C (77—95°F).
Operate the air conditioning system in this condi-
tion until the conditions of the high and low pres-
sure gauges and thermometers are stabilized.
Reading the standard performance curve
1. Read the inlet temperature an get the relative hu-
midity from the psychrometric chart.
2. Read the cool air temperature at the air outlet.
3. Determine the difference between the inlet and out-
let dry-bulb temperature.
4. For example, when the difference is 17°C (30.6°F)
and the relative humidity is 60%:
If
the closing point is the upper part of the line, cool-
ing performance is satisfactory.
76G16X-634
READING THE GRAPH: After reading the temperatures of the wet-and dry-bulb thermometers at the evapo-rator air inlet, the relative humidity (%} can be determined Example: If the dry- and wet-bulb temperatures at the evaporator air inlet are 25°
C
and 19 5°C respectively, find the point of intersection of the dotted lines in the graph, which is
• i
•.p-I--!1. fi -GL^TIULB ': "'.L .T.L CL
16—12
RECEIVER-DRIER 16
RECEIVER-DRIER
ON-VEHICLE INSPECTION
1. Use a leak detector to check the sight glass, the
fusible plug, and the fittings for leakage.
Repair or replace, if necessary.
2. Check the receiver-drier for clogging.
a) Run the engine at fast idle with the air conditioner
on.
b) Check both inlet and outlet temperatures.
If there is a great difference between the two tem-
peratures, replace the receiver-drier.
76G16X-622
Receiver-drier
Condenser bolt
76G16X-638
REMOVAL OF RECEIVER-DRIER
1. Discharge the air conditioning system.
(Refer to page 16—9)
2. Disconnect the two liquid line pipes from the
receiver-drier.
Note:
Plug the open fittings immediately to keep
moisture out of the system.
3. Remove the receiver-drier from the bracket.
INSTALLATION OF RECEIVER-DRIER
1. Install the receiver-drier onto the bracket.
Note:
Do not remove the blind plugs until ready for
connection.
2. Connect the two liquid line pipes to the
receiver-drier.
Tightening torque:
15—25 N m (1.5—2.5 m-kg, 11—18 ft-lb)
3.
If
the receiver-drier is replaced with a new one, add
compressor oil to the compressor.
Compressor oil: 10 cc (0.61 cu in)
16-25