1999 TOYOTA CAMRY clutch switch

± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±9
2491 Author: Date:
3. INSPECT IDLE±UP SPEED
(a) Warm up engine.
(b) Inspect idle±up speed when the these conditions are es-
tablished.

Warm up engine

Blower speed control switch at ºHIº position

A/C switch ON

Temperature control dial at ºCOOLº position
Magnetic clutch conditionIdle±up speed
Magnetic clutch not engaged700 ± 50 rpm
Magnetic clutch engaged700 ± 50 rpm
If idle speed is not as specified, check ISC valve and air intake
system.
4. INSPECT FOR LEAKAGE OF REFRIGERANT
(a) Perform in these conditions:

Stop engine.

Secure good ventilation (If not the gas leak detector
may react to volatile gases witch are not refrigerant,
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 stopped, leave the cooling unit for
more than 15 minutes.

Expose the gas leak detector sensor the 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
blower resistor 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.

AC0LL±02
Z19146
1MZ±FE engine:
No. 1 Engine Coolant Temperature
(ECT) Switch
Compressor
Engine Room Junction Block No. 2

Engine Main Relay
(Marking: ENGINE MAIN)

No. 1 Cooling Fan Relay
(Marking: FAN NO.1)Engine Room Relay Block No. 1

Magnetic Clutch Relay
(Marking: MG CLT)

Heater Main Relay
(Marking: HTR)

No. 2 Cooling Fan Relay
(Marking: FAN NO.2)

No. 3 Cooling Fan Relay
(Marking: FAN NO.3)
5S±FE engine models:
Engine Coolant Temperature
(ECT) Switch Receiver Pressure SwitchCondenser Fan

Fan Motor1MZ±FE engine:
No. 2 Engine Coolant Temperature
(ECT) Switch
Condenser
Blower Unit A/C Unit
A/C Control Assembly

A/C Switch

Blower Speed Control Switch

Mode Switch
Air Outlet Servomotor
Heater Radiator
Thermistor
Blower ResistorBlower Motor 1MZ±FE:
A/C Amplifier Expansion Valve5S±FE engine:
ECM (Built in A/C Amplifier)
Evaporator
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±13
2495 Author: Date:
LOCATION

AC21T±01
AC±14
± AIR CONDITIONINGTROUBLESHOOTING
2496 Author: Date:
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
4. HTR Fuse
5. Heater main relay
6. Blower motor
7. Blower resistor
8. Blower speed control switch
9. Wire harness±
AC±70
AC±63
AC±64
AC±84
±
No air temperature control1. Engine coolant volume
2. A/C control assembly±
AC±80
No air inlet control1. A/C control assemblyAC±80
No air outlet control
1. HTR Fuse
2. Air outlet servomotor
3. Mode switch±
AC±65
AC±84
No compressor operation
1. Refrigerant volume
2. A.C Fuse
3. HTR Fuse
4. Magnetic clutch relay
5. Magnetic clutch
6. Compressor
7. Pressure switch
8. Heater main relay
9. Blower speed control switch
10.A/C switch
11. *1 ECM
*
2 A/C amplifier
12.Wire harness
AC±3
±
±
AC±71
AC±39
AC±39
AC±67
AC±70
AC±84
AC±84
DI±218
AC±88
±
No compressor operates intermittently
1. Refrigerant volume
2. Condenser fan
3. Pressure switch
4. *1 ECM
*2 A/C amplifier
5. Thermistor
6. Wire harnessAC±3
AC±74
AC±67
DI±218
AC±88
AC±24
±
No cool air comes out
1. Refrigerant volume
2. Refrigerant pressure
3. Drive belt
4. Compressor lock sensor
5. Magnetic clutch
6. Compressor
7. Pressure switch
8. Thermistor
9. A/C switch
10.*1 ECM
*2 A/C amplifier
11. Wire harnessAC±3
AC±3
AC±16
AC±16
AC±39
AC±39
AC±67
AC±24
AC±84
DI±218
AC±88
±

± AIR CONDITIONINGTROUBLESHOOTING
AC±15
2497 Author: Date:
Cool air comes out only at high engine rpm
1. Refrigerant volume
2. Drive belt
3. Magnetic clutch
4. Compressor
5. Condenser
6. Condenser fan
7. Receiver
8. Expansion valve
9. Evaporator
10.Thermistor
11. Refrigerant line
12.Pressure switch
13.*
1 ECM
*2 A/C amplifier
AC±3
AC±16
AC±16
AC±39
AC±52
AC±74
AC±49
AC±59
AC±30
AC±24
AC±21
AC±67
DI±218
AC±88
No engine idle±up when A/C switch ON
1. *1 ECM
*2 A/C amplifier
2. Wire harness
DI±218
AC±88
±
Blinking of A/C indicator
1. *1 ECM
*2 A/C amplifier
2. Thermistor
3. Compressor
DI±218
AC±88
AC±24
AC±39
A/C indicator does not lights up when turn mode switch to DEF.
position
1. A/C Fuse
2. Mode switch
3. A/C switch
4. *
1 ECM
*2 A/C amplifier
5. Wire harness
±
AC±84
AC±84
DI±218
AC±88
±
No warm air comes out
1. Engine coolant volume
2. A/C control assembly
3. Heater radiator±
AC±80
AC±57
No condenser fan operation
1. CDS 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. Condenser fan motor
7. Pressure switch
8. *
1 Engine coolant temp. switch
*2 No. 1 Engine coolant temp. switch
9. *2No. 2 Engine coolant temp. switch
10.Wire harness
±
±
AC±72
AC±72
AC±72
AC±74
AC±67
AC±92
AC±92
AC±92
±
*1: 5S±FE Engine Models
*
2: 1MZ±FE Engine Models

AC0M4±02
N01143
W
N01150
± AIR CONDITIONINGCOMPRESSOR AND MAGNETIC CLUTCH
AC±39
2521 Author: Date:
COMPRESSOR AND MAGNETIC
CLUTCH
ON±VEHICLE INSPECTION
1. INSPECT COMPRESSOR FOR METALLIC SOUND
(a) Start engine.
(b) Check if there is a metallic sound from the compressor
when the A/C switch is on.
If metallic sound is heard, replace the compressor assembly.
2. INSPECT REFRIGERANT PRESSURE
See ºON±VEHICLE INSPECTIONº of AIR CONDITIONING
SYSTEM on page AC±3.
3. INSPECT COMPRESSOR LOCK SENSOR RESIS-
TANCE
(a) Disconnect the connector.
(b) Measure resistance between terminals 1 and 2.
Standard resistance: 65 ± 125 W at 20 °C (68 °F)
If resistance is not as specified, replace the compressor assem-
bly.
4. INSPECT VISUALLY FOR LEAKAGE OF REFRIGER-
ANT FROM SAFETY SEAL
Using a gas leak detector, check for leakage of refrigerant.
If there is any leakage, replace the compressor assembly.
5. CHECK FOR LEAKAGE OF GREASE FROM CLUTCH
BEARING
6. CHECK FOR SIGNS OF OIL ON PRESSURE PLATE OR
ROTOR
7. INSPECT MAGNETIC CLUTCH BEARING FOR NOISE
(a) Start engine.
(b) Check for abnormal noise from near the compressor
when the A/C switch is OFF.
If abnormal noise is being emitted, replace the magnetic clutch.
8. INSPECT MAGNETIC CLUTCH OPERATION
(a) Disconnect the connector.
(b) Connect the positive (+) lead from the battery to terminal
4 and the negative (±) lead to the body ground.
(c) Check that the magnetic clutch is energized.
If operation is not as specified, replace the magnetic clutch.

AC0M4±02
N01143
W
N01150
± AIR CONDITIONINGCOMPRESSOR AND MAGNETIC CLUTCH
AC±39
2521 Author: Date:
COMPRESSOR AND MAGNETIC
CLUTCH
ON±VEHICLE INSPECTION
1. INSPECT COMPRESSOR FOR METALLIC SOUND
(a) Start engine.
(b) Check if there is a metallic sound from the compressor
when the A/C switch is on.
If metallic sound is heard, replace the compressor assembly.
2. INSPECT REFRIGERANT PRESSURE
See ºON±VEHICLE INSPECTIONº of AIR CONDITIONING
SYSTEM on page AC±3.
3. INSPECT COMPRESSOR LOCK SENSOR RESIS-
TANCE
(a) Disconnect the connector.
(b) Measure resistance between terminals 1 and 2.
Standard resistance: 65 ± 125 W at 20 °C (68 °F)
If resistance is not as specified, replace the compressor assem-
bly.
4. INSPECT VISUALLY FOR LEAKAGE OF REFRIGER-
ANT FROM SAFETY SEAL
Using a gas leak detector, check for leakage of refrigerant.
If there is any leakage, replace the compressor assembly.
5. CHECK FOR LEAKAGE OF GREASE FROM CLUTCH
BEARING
6. CHECK FOR SIGNS OF OIL ON PRESSURE PLATE OR
ROTOR
7. INSPECT MAGNETIC CLUTCH BEARING FOR NOISE
(a) Start engine.
(b) Check for abnormal noise from near the compressor
when the A/C switch is OFF.
If abnormal noise is being emitted, replace the magnetic clutch.
8. INSPECT MAGNETIC CLUTCH OPERATION
(a) Disconnect the connector.
(b) Connect the positive (+) lead from the battery to terminal
4 and the negative (±) lead to the body ground.
(c) Check that the magnetic clutch is energized.
If operation is not as specified, replace the magnetic clutch.

N20291
AC0N2±02
Z13470
Magnetic clutch control
Low pressure side
ON (Continuity)
196 kPa
(2.0 kgf/cm
2, 28 psi)High pressure side
3, 140 kPa
(32.0kgf/cm2, 455 psi)
OFF (No Continuity)
Z13471
1, 226 kPa
(12.5 kgf/cm2, 178 psi)OFF
(No Continuity) Condenser fan control
ON
(Continuity)150 kPa
(15.5 kgf/cm
2, 220 psi)
± AIR CONDITIONINGPRESSURE SWITCH
AC±67
2549 Author: Date:
PRESSURE SWITCH
ON±VEHICLE INSPECTION
1. SET ON MANIFOLD GAUGE SET
(See page AC±19)
2. DISCONNECT CONNECTOR FROM PRESSURE
SWITCH
3. RUN ENGINE AT APPROX. 1,500 RPM
4. Magnetic clutch control:
INSPECT PRESSURE SWITCH OPERATION
(a) Connect the positive (+) lead from the ohmmeter to termi-
nal 4 and negative (±) lead to terminal 1.
(b) Check continuity between terminals when refrigerant
pressure is changed, as shown in the illustration.
If operation is not as specified, replace the pressure switch.
5. Condenser fan control:
INSPECT PRESSURE SWITCH OPERATION
(a) Connect the positive (+) lead from the ohmmeter to termi-
nal 2 and negative (±) lead to terminal 3.
(b) Check continuity between terminals when refrigerant
pressure is changed, as shown in the illustration.
If operation is not as specified, replace the pressure switch.
6. STOP ENGINE AND REMOVE MANIFOLD GAUGE
SET
7. CONNECT CONNECTOR TO PRESSURE SWITCH

Z13473
From back side:
± AIR CONDITIONINGAIR CONDITIONING AMPLIFIER
AC±89
2571 Author: Date:
(b) Connect the connector to amplifier and inspect wire har-
ness side connector from the back side, as shown in the
chart below.
Test conditions:

Running engine at idle speed

Blower speed switch HI

A/C switch ON

Temperature control lever Max Cool

Set on manifold gauge set
Tester connectionConditionSpecified condition
1 ± GroundMagnetic clutch is not engagedBelow 1.0 V
1 ± GroundMagnetic clutch is engagedNo voltage
7 ± GroundMagnetic clutch is not engagedBelow 1.0 V
7 ± GroundMagnetic clutch is engagedBattery positive voltage
2 ± GroundRefrigerant pressure 196 ± 1,340 kPaBattery positive voltage
2 ± GroundRefrigerant pressure
less than 196 or more than 3,140 kPaNo voltage
12 ± GroundRefrigerant pressure 196 ± 1,340 kPaBelow 1.0 V
12 ± GroundRefrigerant pressure
less than 196 or more than 3,140 kPaBattery positive voltage
12 ± GroundEngine coolant temp. 83°C (181°F) or belowBattery positive voltage
12 ± GroundEngine coolant temp. 93°C (199°F) or aboveBelow 1.0 V
If circuit is as specified, try replacing the amplifier with a new
one. If the circuit is not as specified, inspect the circuits con-
nected to other parts.