1986 TOYOTA CAMRY V20 ignition

Ignition Switch ºONº
Blower Switch º'ONº " Heater Relay ªONº (Blower Motor ºRUNº)
A/C Switch ºONº " A/C Amplifier º'ONº (A/C Amp. Main Power Supply) 1. PRINCIPLE OF A/C ELECTRICAL CIRCUIT
2. HOW IS MAGNETIC CLUTCH ENERGIZED?
The general process until the magnetic clutch is energized is shown below.
Dual Pressure Switch º'ONº:
Refrigerant Condition (2.1 kg/cm2 (30 psi, 206 kPa) less than 27 kg/cm
2 (384 psi, 2,648 kPa))
Thermistor supplies temperature signal of evaporator to A/C amplifier.
VSV ºONº " E/G Idle±Up
Magnetic Clutch Relay º'ONº
Temperature Sensor ºONº:
Temperature of Temperature Sensor is less than 180
°C (356°F).
Magnetic Clutch ºONº
Revolution Detecting Sensor supplies RPM signal of compressor to A/C amplifier.
If compressor is not locked, magnetic clutch is continuously energized.
± AIR CONDITIONING SYSTEMGeneral DescriptionAC±14

AMPLIFIERS
Inspection of Amplifier
(See page AC±12)
Air Conditioner Amplifier
INSPECT AMPLIFIER CIRCUIT
Disconnect the amplifier and inspect the connector on the
wire harness side as shown in the chart below.
Test conditions:
(1) Ignition: ON
(2) Temperature control lever: MAX. COOL
(3) Blower switch: Hl
If circuit is as specified, replace the amplifier.
ApProx. 1.7 k
at 25°C (77°F)
3S±FE Engine Model
Turn ignition switch off.Turn ignition switch on.
Turn ignition switch off.Turn ignition switch on.
Turn ignition switch off.
Turn ignition switch on.Turn A/C switch off.
Turn A/C switch on.
Turn A/C switch off.Turn A/C switch on.
4pprox. 10 to 14 V
Tester
connectionSpecified value
Battery voltage
Battery voltageBattery voltageBattery voltage
Battery voltage
ApproX. 250 W Start engine.
Stop engine.No voltageNo voltage
No voltage
No voitage
No voltageNo voltage ContinuityContinuity
Resistance
Condition
Check for
Constant
ConstantConstant
Voltage
Voltage
± AIR CONDITIONING SYSTEMAmplifiersAC±45

Condenser Fan Control Amplifier
INSPECT AMPLIFIER CIRCUIT
Disconnect the amplifier and inspect the connector on the
wire harness side as shown in the chart below. If the circuit is as specified, replace the amplifier.
If circuit is as specified, replace the amplifier. 2VZ±FE Engine Model
Approx. 1.5 k
at 27°C (77°F)
Turn ignition switch off.
Turn ignition switch off. Turn ignition switch on±. Turn ignition switch on. Turn ignition switch off.Turn ignition switch on. Turn ignition switch off. Turn ignition switch on.
Turn A/C switch on.
Turn A/C switch on.
Turn A/C switch off. Turn A/C switch off.
Tester
connection
Approx. 10 to 14 V Tester
connection
Specified valueSpecified value
Battery voltageBattery voltageBattery voltage Battery voltage
Battery voltage
Approx. 250
Battery voltage
Start engine.
Stop engine.
No voltageNo voltage
No voltage
No voltage
No voltage ContinuityNo voltageNo voltage
ContinuityContinuity
Continuity Continuity
Continuity
Condition
Continuity ResistanceCondition
Check forCheck for
Constant Constant Constant
Constant Constant
Constant Constant
VoltageVoltage
± AIR CONDITIONING SYSTEMAmplifiersAC±46

Compressor Control Amplifier
INSPECT AMPLIFIER CIRCUIT
Disconnect the amplifier and inspect the connector on the
wire harness side as shown in the chart below.
VACUUM HOSE CIRCUIT (3S±FE Engine)
Approx. 4.4 k
25°C(77°F) Turn ignition switch on.
Turn ignition switch off.
Tester
connectionSpecified value
3 ± GroundBattery voltage 6 ± Ground
No voltage ContinuityContinuity
Resistance
Condition
Check for
Constant Constant
Voltage
5±7
± AIR CONDITIONING SYSTEMAmplifiersAC±47

Compressor Control Amplifier
INSPECT AMPLIFIER CIRCUIT
Disconnect the amplifier and inspect the connector on the
wire harness side as shown in the chart below.
VACUUM HOSE CIRCUIT (3S±FE Engine)
Approx. 4.4 k
25°C (77°F) Turn ignition switch on.
Turn ignition switch off.
Tester
connectionSpecified value
3 ± GroundBattery voltage 6 ± Ground
No voltage ContinuityContinuity
Resistance
Condition
Check for
Constant Constant
Voltage
5±7
± AIR CONDITIONING SYSTEMVacuum Hose CircuitAC±47

Diagnosis System (A140E)
DESCRIPTION
1. A self±diagnosis function is built into the electrical control system.
Warning is indicated by the overdrive OFF indicator.
HINT: Warning and diagnostic codes can be read only when
the overdrive switch is ON. If OFF, the overdrive OFF
indicator is lit continuously and will not blink.
(a) If a malfunction occurs within the speed sensors (No.
1 or 2) or solenoids (No. 1 or 2), the overdrive OFF
light will blink to. warn the driver. .
However, there will be no warning of a malfunction with
lock±up solenoid.
(b) The diagnostic code can be read by the number of blinks of
the overdrive OFF indicator when terminals
Tt and E1 are short±circuited. (See page AT±17)
tc) The throttle position sensor or brake signal are not indi-
cated, but inspection can be made by checking the voltage at
terminal Tt of the check connector (diagnosis).
(d) The signals to each gear can be checked by measuring the
voltage at terminal Tt of the check connector while driving.
2. The diagnostic (malfunction) code is retained in memory by the
CPU and due to back±up voltage, is not canceled out when the
engine is turned off. Consequently, after repair, it is necessary
to turn the ignition switch off and remove the fuse EFI (15A) or
disconnect the ECT computer connector to cancel out the diag-
nostic (malfunction)
code. (See page AT±18)
HINT:
wLow battery voltage will cause faulty operation of the diag-
nosis system. Therefore, always check the battery first.
w Use a voltmeter and ohmmeter that have an impedance
of at least 10 k 11 IV.
CHECK O/D OFF INDICATOR LIGHT
1. Turn the ignition switch ON.
2. The O/D OFF light will come on when the O/D switch is
placed at OFF.
3. When the O/D switch is set to ON, the O/D OFF light
should go out.
If the O/D OFF light flashes when the O/D switch is set
to ON, the electronic control system is faulty.
± AUTOMATIC TRANSAXLETroubleshooting (Diagnosis System) (A140E)AT±16

wIn the event of a malfunction, the fight will blink once every
0.5 seconds. The number of blinks will equal the first num-
ber and, after 1.5 seconds pause, the second number of the
two digit diagnostic code. If there are two or more codes,
there will be a 2.5 seconds pause between each.
HINT: In the event of several trouble codes occurring
simultaneously, indication will begin from the smaller
value and continue to the larger.
4. REMOVE SST
SST 09843±18020
READ DIAGNOSTIC CODE
1. TURN IGNITION SWITCH AND O/D SWITCH TO ON
Do not start the engine.
HINT: Warning and diagnostic codes can be read only
when the overdrive switch is ON. If OFF, the overdrive OFF
light will light continuously and will not blink.
2. SHORT ECT TERMINAL CIRCUIT OF CHECK
CONNECTOR
Using a SST, short terminals Tt and E1 of the check
connector.
SST 09843±18020
(Diagnostic Code Indication)
wIf the system is operating normally, the light will
blink once every 0.25 seconds. 3. READ DIAGNOSTIC CODE
Read the diagnostic code as indicated by the number
of times the O/D OFF indicator flashes.
± AUTOMATIC TRANSAXLETroubleshooting (Diagnosis System) (A140E)AT±17

CANCEL OUT DIAGNOSTIC CODE
1. After repair of the trouble area, the diagnostic code
retained in memory by the ECT ECU must be canceled by
removing the fuse EFI (15A) for 10 seconds or more, de-
pending on ambient temperature (the lower the tempera-
ture, the longer the fuse must be left out) with the ignition
switch OFF.
HINT:
wCancellation can be also done by removing the battery
negative (±) terminal, but in this case other memory sys-
tems (TCCS diagnosis memory, etc.) will be also can-
celed out.
wThe diagnostic code can be also canceled out by discon-
necting the ECT ECU connector.
wIf the diagnostic code is not canceled out, it will be
retained by the ECT ECU and appear along with a new
code in event of future trouble.
2. After cancellation, perform a road test to confirm that a
ºnormal codeº is now read on the O/D OFF indicator. HINT: If codes 62, 63 or 64 appear, there is an
electrical malfunction in the solenoid.
Causes due to ±mechanical failure, such as a
stuck valve, will not appear.
Defective No. 1 speed sensor (in combination meter) ±
severed wire harness or short circuit
Severed lock±up solenoid or short circuit ±
severed wire harness or short circuit Defective No. 2 speed sensor (in ATM) ±
severed wire harness or short circuit
Severed No. 2 solenoid or short circuit ±
severed wire harness or short circuitSevered No. 1 solenoid or short circuit ±
severed wire harness or short circuit
DIAGNOSTIC CODES
Diagnosis System
Light Pattern Code No.
Normal
± AUTOMATIC TRANSAXLETroubleshooting (Diagnosis System) (A140E)AT±18