TOYOTA SUPRA 1995 Service User Guide

USE OF MANIFOLD GAUGE SET
MANIFOLD GAUGE SET INSTALLATION
1. CONNECT CHARGING HOSES TO MANIFOLD GAUGE
SET
Tighten the nuts by hand.
CAUTION: Do not connect the wrong hoses.
2. CONNECT QUICK CONNECTORS TO CHARGING HOSES
Tighten the nuts by hand.
3. CLOSE BOTH HAND VALVES OF MANIFOLD GAUGE
SET
4. REMOVE CAPS FROM SERVICE VALVES ON
REFRIGERANT LINE
5. CONNECT QUICK CONNECTORS TO SERVICE VALVES
HINT: Push the quick connector onto the service valve, then
slide the sleeve of the quick connector downward to lock it.
MANIFOLD GAUGE SET REMOVAL
1. CLOSE BOTH HAND VALVES OF MANIFOLD GAUGE
SET
2. DISCONNECT QUICK CONNECTORS FROM SERVICE
VALVES ON REFRIGERANT LINE
HINT: Slide the sleeve of the quick connector upward to un-
lock the connector and remove it from the service valve.
3. INSTALL CAPS TO SERVICE VALVES ON REFRIGERANT
LINE
± AIR CONDITIONING SYSTEMUSE OF MANIFOLD GAUGE SETAC±11

±MEMO±
AC±12± AIR CONDITIONING SYSTEMUSE OF MANIFOLD GAUGE SET

TROUBLESHOOTING
± AIR CONDITIONING SYSTEMTROUBLESHOOTINGAC±13

HOW TO PROCEED WITH TROUBLESHOOTING
Perform troubleshooting in accordance with the procedure on the following page.
P. AC±16
P. IN±24
P. AC±19
P. AC±19P. AC±26
P. AC±28 ~ AC±70
Vehicle Brought to Workshop
Customer Problem Analysis
Check and Clear Trouble Code (Precheck)
Problem Symptom Confirmation Symptom Simulation
Trouble Code Check
Trouble Code ChartMatrix Chart of Problem Symptoms
Circuit InspectionActuator CheckPart Inspection
Identification of Problem
Repair
End
Confirmation Test
P. AC±19
Items insideare titles of pages in this
manual, with the page number indicated in the bottom
portion. See the indicated pages for detailed explana-
tions.
AC±14± AIR CONDITIONING SYSTEMTROUBLESHOOTING

CUSTOMER PROBLEM ANALYSIS CHECK SHEET
 AIR CONDITIONING SYSTEM Check Sheet
± AIR CONDITIONING SYSTEMTROUBLESHOOTINGAC±15

PANEL DIAGNOSIS SYSTEM
If a trouble occurs in A/C system, the specified lamp on the control panel starts blinking during the diagnos-
tic sensor check.
During system diagnosis, a trouble is indicated on the panel by the blinking of a specified light instead of
a code display. (See TROUBLE CODE CHART)
For example, when a trouble occurs in solar sensor circuit, the LED for DEF mode switch will be blinking
during the diagnostic sensor check.
SWITCH
SWITCH NAMECODECODESWITCH NAMECODESWITCH NAME
LED
INDICATOR NAMECODEINDICATOR NAMECODEINDICATOR NAMECODE
AC±16± AIR CONDITIONING SYSTEMTROUBLESHOOTING

Warning for A/C compressor lock
If compressor lock occurs during air conditioning operation,
the [A/C] switch indicator on the air conditioning control as-
sembly starts blinking.
When this occurs, check for compressor lock using panel
diagnosis check then proceed to inspect the circuit or the
component.
Compressor lock sensor circuit " page AC±38
LIST OF OPERATION METHODS
By operating each of the air conditioning control switches as shown in the diagram below, it is possible to
enter the diagnosis check mode.
Indicator Check
Diagnostic
Sensor Check
(continuous operation)
Diagnostic
Sensor Check
(stepped operation)
Cancel check mode and can start
conditioning control
Actuator Check
(continuous
operation)
Turn ignition switch ON with AUTO and
switches held down.
If both Auto switch and switch are
not pressed at the same time.
: Indicates a switch operation
± AIR CONDITIONING SYSTEMTROUBLESHOOTINGAC±17

INDICATOR CHECK
1. Turn the ignition switch on while pressing the air conditioning
control AUTO switch and R/F SW simultaneously.
2. Check that all the indicators light up and go off at 1
second intervals 4 times in succession.
HINT:
wAfter the indicator check is ended, the diagnostic sensor
check begins automatically.
wPress the OFF switch when cancelling the check mode.
DIAGNOSTIC SENSOR CHECK
1. Perform an indicator check. After the indicator check is
completed, the system enters the diagnostic sensor check
mode automatically.
2. Check the LED blinking on the panel. Refer to the list of codes
on page AC±20 when translating the trouble code from the
LED blinking.
If the slower display is desired, press the RDEF switch and
change it to step operation. Each time the RDEF switch is
pressed, the blinking LED changes by 1 step.
CLEARING TROUBLE CODES' MEMORY
Method 1:
1. Pull out the ECU±B fuse in Junction Block No. 1 for 10 sec.
or longer to clear the trouble codes' memory.
2. After reinserting the fuse, check that the normal code is
output.
Method 2:
Press the RDEF switch while pushing the A/C switch during
the sensor check mode. AC±18
± AIR CONDITIONING SYSTEMTROUBLESHOOTING

±MEMO±
± AIR CONDITIONING SYSTEMTROUBLESHOOTINGAC±19

SENSOR CHECK TROUBLE CODE CHART
If a LED is blinking during the diagnostic sensor check, check the circuit listed for the code in the table below
(Proceed to the page given for that circuit.)
 
 No.
 
 Blinking LED
 
 Detecting Condition
 0 L±AUTO 
Normal
 1 L±FACE*1 
Open or short in room temperature sensor circuit.
 2 L±B/L 
Open or short in ambient temperature sensor circuit.
 3 L±FOOT 
Open or short in evaporator temperature sensor circuit.
 4 L±F/D*2 
Open or short in engine coolant temperature sensor circuit.
 
5
 
L DEF*3 
Open in solar sensor circuit.
 5 L±DEF*3 
Short in solar sensor circuit.
 
 
 
6
 
 
 
L±A/C*4
 
 
 

All conditions below are detected for 3 secs. or more.
(a) Engine speed 450 rpm or more.
(b) Ratio between engine and compressor rpm deviates 20% or more in comparison to normal operation.
 
 

7
 
 

L±FRS
 
 


Open in pressure sensor circuit.

Abnormal refrigerant pressure [ below 196 kPa (2.0 kgf/cm2, 28 psi)
over 3,140 kPa (32.0 kgf/cm2, 455 psi) ] 
 8
 
 L±REC
 
 
Short to ground or power source circuit in air mix damper position sensor circuit.
 9 L±LO 
Short to ground or power source circuit in air outlet damper position sensor circuit.
 10 L±M2 
Air mix damper position sensor value does not change even if A/C amplifier signals the
air mix damper control servo motor to operate.
 
 11
 
 L±HI
 
 
Air outlet damper position sensor value does not change even if A/C amplifier signals the
air outlet damper control servo motor to operate.
HINT: *1If the room temp. is approx. ±20°C (±4°F) or lower, FACE light may blink even though the
system is normal.
*
2If the ambient temperature is approx. ±50°C (±58°F) or lower, the B/L light may blink even
though the system is normal.
*
3If the check is being performed in a dark place, the LED for DEF (solar sensor circuit abnormal)
could be blinking.
In this case, perform diagnostic sensor check again while shining a light, such as an inspection
light, on the solar sensor.
If the light is still blinking, there could be trouble in the solar sensor circuit. AC±20
± AIR CONDITIONING SYSTEMTROUBLESHOOTING