1995 TOYOTA SUPRA heater

HINT:
wIf the instruction ºProceed to next circuit inspection shown on matrix chart is given in the flow chart
for each circuit, proceed to the circuit with the next highest number in the table to continue the check.
wIf the trouble still reappears even though there are no abnormalities in any of the other circuits, then
check or replace the A/C amplifier.
AC±52
AC±54
AC±56
AC±58
AC±60
AC±62
AC±66
AC±69
IN±35
AC±71
AC±76
AC±77
AC±107
AC±92
AC±91
AC±95
AC±96
AC±98
AC±97
IG power source circuitBackup power source
circuitACC power source circuitHeater relay circuitCompressor circuitBlower motor circuitA/C amplifierTemperature set dial circuitA/C control assembly circuitRefrigeration system inspection
with manifold gauge setElectric cooling fanWater valveDrive belt tensionRefrigerant volumeCondenserExpansion valveEvaporatorHeater radiatorReceiver
± AIR CONDITIONING SYSTEMTROUBLESHOOTINGAC±27

Heater Relay Circuit
CIRCUIT DESCRIPTION
The heater relay is switched on by signals from the A/C amplifier and switches power to the blower motor.
AC±58± AIR CONDITIONING SYSTEMTROUBLESHOOTING

Check voltage between terminal HR of A/C amplifier connector and
body ground.
Check heater relay.
Proceed to next circuit inspection shown on matrix
chart (See page AC±26).
Check HTR fuse.
Check and repair harness and connector between
A/C amplifier and battery.
Check for short in all the harness and compo-
nents to the HTR fuse (See attached wiring
diagram).
Replace heater relay.
Remove the A/C amplifier with connectors still con-
nected
Measure voltage between terminals HR of A/C ampli-
fier connector and body ground when ignition switch is
ON and OFF.
VoltageIgnition Switch
Check continuity between each pair of terminals of
heater relay shown below.
1. Apply battery positive voltage between terminals
1 and 3.
2. Check continuity between each pair of terminal
shown below.
Terminals 2 and 4
Terminals 4 and 5
No continuity
Continuity
Terminals 4 and 5
Terminals 1 and 3
Terminals 2 and 4
No continuity
Continuity
OFF
ON
OV
Blower OFF
Blower ON Below 1.O V
Battery positive
voltage
INSPECTION PROCEDURE
± AIR CONDITIONING SYSTEMTROUBLESHOOTINGAC±59

AIR CONDITIONING UNIT
AIR CONDITIONING UNIT REMOVAL
1. DISCHARGE REFRIGERANT IN REFRIGERATION
SYSTEM
INSTALLATION HINT: Evacuate air from refrigeration sys-
tem.
Charge system with the refrigerant and inspect for leakage
of refrigerant.
Specified amount:
700 + 50 g (24.96 + 1.76 oz.)
2. DRAIN ENGINE COOLANT FROM RADIATOR AND
ENGINE COOLANT DRAIN COCK
3. REMOVE ENGINE WIRE HARNESS BRACKET
MOUNTING BOLT
4. REMOVE BRAKE TUBE BRACKET MOUNTING BOLTS
FROM DASH PANEL
5. REMOVE WATER HOSE FROM HEATER RADIATOR
6. REMOVE INSULATOR RETAINER
Remove the 2 bolts and the insulator retainer.
7. REMOVE LIQUID TUBE AND SUCTION TUBE
(a) w/ ABS:
Remove the ABS actuator.
(See page BR±44)
(b) Remove the liquid tube and suction tube.
Torque: 10 NVm (100 kgfVcm, 7 ftVlbf)
INSTALLATION HINT: Lubricate the new O±rings with com-
pressor oil and install tubes.
8. REMOVE PLATE COVER
Remove the 2 bolts and the plate cover.
9. REMOVE INSTRUMENT PANEL AND REINFORCEMENT
(See page BO±45) AC±80
± AIR CONDITIONING SYSTEMAIR CONDITIONING UNIT

10. REMOVE HEATER TO REGISTER NO. 3 DUCT
Remove the 3 screws and the heater to register No. 3 duct.
11. REMOVE A/C UNIT
(a) Disconnect connectors from the unit.
(b) Remove the 6 bolts and the A/C unit.
INSTALLATION HINT: Pull the drain hose of the A/C unit for-
ward until the yellow paint on the hose is visible in the engine
compartment.
Insert the drain hose into the engine compartment hose until
the matchmarks are aligned.
± AIR CONDITIONING SYSTEMAIR CONDITIONING UNITAC±81

5. REMOVE AIR MIX SERVOMOTO
(a) Remove the defroster duct.
(b) Remove the 3 screws and the water valve cover.
(c) Disconnect the connector.
(d) Disconnect the control link.
(e) Remove the 2 screws and the air mix servomotor.
6. REMOVE HEATER RADIATOR AND WATER VALVE
(a) Remove the 2 screws and the plate.
(b) Remove the 2 screws and the clamp.
(c) Remove the 3 screws.
(d) Pull out the heater radiator with the water valve.
(e) Remove the 2 screws and water valve from the heater
radiator.
7. REMOVE HEATER AIR DUCT
Remove the 2 screws and the defroster air duct.
8. REMOVE VENT AIR DUCT
(a) Disconnect the control link.
(b) Remove the 2 screws and the vent air duct.
9. REMOVE ENGINE COOLANT TEMPERATURE SENSOR
(a) Disconnect the connector.
(b) After pulling off the clamp, pull out the sensor.
10. REMOVE AIR OUTLET SERVOMOTOR
(a) Disconnect the connector.
(b) Remove the 3 screws and the air outlet servomotor. AC±84
± AIR CONDITIONING SYSTEMAIR CONDITIONING UNIT

EVAPORATOR INSPECTION
1. INSPECT FINS FOR BLOCKAGE
If the fins are clogged, clean them with compressed air.
NOTICE: Never use water to clean the evaporator.
2. INSPECT FITTING FOR CRACKS OR SCRATCHES
Repair as necessary.
EVAPORATOR INSTALLATION
Installation is in the reverse order of removal.
HEATER RADIATOR
HEATER RADIATOR REMOVAL AND
INSTALLATION
(See page AC±82)
HEATER RADIATOR INSPECTION
INSPECT FINS FOR BLOCKAGE
If the fins are clogged, clean them with compressed air. AC±96
± AIR CONDITIONING SYSTEMHEATER RADIATOR

WATER VALVE
WATER VALVE REMOVAL
1. REMOVE HEATER RADIATOR
(See page AC±82)
2. REMOVE WATER VALVE
(a) Remove the 2 screws.
(b) Remove the water valve from heater radiator.
WATER VALVE INSTALLATION
1. INSTALL WATER VALVE
(a) Install the water valve to heater radiator.
(b) Install the 2 screws.
2. INSTALL HEATER RADIATOR
± AIR CONDITIONING SYSTEMWATER VALVEAC±97