Page 141 of 4323
PP1AG±08
± PREPARATIONAIR CONDITIONING
PP±83
141 Author: Date:
2005 SEQUOIA (RM1146U)
EQUIPMENT
Voltmeter
Ammeter
Ohmmeter
Test lead
ThermometerSensor
Torque wrench
Dial indicatorMagnetic clutch
Plastic hammerMagnetic clutch
Hexagon wrenchExpansion valve
Page 194 of 4323
SS0O4±05
SS±52
± SERVICE SPECIFICATIONSAIR CONDITIONING
194 Author: Date:
2005 SEQUOIA (RM1146U)
TORQUE SPECIFICATION
Part tightenedN´mkgf´cmft´lbf
REFRIGERANT LINE
Receiver x Liquid tube5.45548 in.´lbf
Condenser x Discharge hose5.45548 in.´lbf
Condenser x Liquid tube5.45548 in.´lbf
Compressor x Discharge hose101007
Compressor x Suction hose101007
Liquid and suction tube (Nut)5.45548 in.´lbf
Liquid and suction tube x Rear A/C unit5.45548 in.´lbf
COOLING UNIT
Evaporator x Expansion valve x Liquid and suction tube3.53631 in.´lbf
REAR A/C UNIT
Tube and accessory x Evaporator5.45531 in.´lbf
Tube and accessory x Expansion valve2223516
Expansion valve x Liquid tube1313510
COMPRESSOR AND MAGNETIC CLUTCH
Compressor x Engine (Bolt)4748035
Compressor x Bracket x Engine (Nut)2525518
Pressure plate x Rotor x Compressor1818412.3
PRESSURE SWITCH
Pressure switch x Liquid tube101007
WATER TEMPERATURE SWITCH
Water temperature switch x Radiator7.47565 in.´lbf
Page 2501 of 4323
DIDKN±01
I28851
R/B No. 2
Heater Main Relay
(Marking: HTR)
Compressor
Condenser
Receiver Pressure Switch
Integration Panel Assembly
A/C ECU
A/C Switch
Air Inlet Selector
Heater Unit
Heater Radiator
Air Mix Servomotor
Air Outlet Servomotor
Cooling Unit
Blower Motor Linear
Controller
Evaporator
Expansion Valve
ThermistorBlower Unit
Blower Motor
Air Inlet Servomotor
Water Valve
Rear Heater
Control Assembly
Condenser Fan
Ambient
Temperature
Sensor
Solar Sensor
Room
Temperature
Sensor
Rear Room Temperature
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2299
2493 Author: Date:
2005 SEQUOIA (RM1146U)
LOCATION
Page 2502 of 4323
I21419
Water Valve
Air Outlet
Servomotor
Heater Radiator
Thermistor
Evaporator
Expansion Valve Power Transistor Blower Motor
DI±2300
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2494 Author: Date:
2005 SEQUOIA (RM1146U)
Page 2506 of 4323

DI3F3±10
DI±2304
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2498 Author: Date:
2005 SEQUOIA (RM1146U)
PROBLEM SYMPTOMS TABLE
Front A/C:
SymptomSuspected AreaSee page
Whole functions of the A/C system do not operate4. Integration control and panel
5. IG power source circuitIN±35
DI±2363
Air Flow Control: No blower operation
1. IG power source circuit
2. Heater main relay
3. Blower motor circuit
4. Integration control and panel
5. Blower motor controllerDI±2363
AC±95
DI±2374
IN±35
AC±83
Air Flow Control: No blower control
1. Blower motor circuit
2. Integration control and panel
3. Solar sensor circuit
4. Blower motor controllerDI±2374
IN±35
DI±2336
AC±83
Air Flow Control: Insufficient air flow1. Blower motor circuitDI±2374
Temperature Control: No cool air comes out
1. Refrigerant volume
2. Drive belt tension
3. Refrigeration system inspection with manifold gauge set
4. Compressor circuit
5. Pressure switch circuit
6. Front air mix damper position sensor circuit
7. Front air mix damper control servomotor circuit
8. Front room temp. sensor circuit
9. Ambient temp. sensor circuit
10.Vehicle speed signal circuit
11. Integration control and panelAC±23
AC±15
AC±3
DI±2381
DI±2342
DI±2346
DI±2355
DI±2319
DI±2322
DI±2370
IN±35
Temperature Control: No warm air comes out
1. Front air mix damper position sensor circuit
2. Front air mix damper control servomotor circuit
3. Front room temp. sensor circuit
4. Ambient temp. sensor circuit
5. Vehicle speed signal circuit
6. Front evaporator temp. sensor circuit
7. Integration control and panelDI±2346
DI±2355
DI±2319
DI±2322
DI±2370
DI±2325
IN±35
Temperature Control: Output air is warmer or cooler than the set
temperature or response is slow
1. Refrigerant volume
2. Drive belt tension
3. Refrigeration system inspection with manifold gauge set
4. Cooling fan system
5. Solar sensor circuit
6. Front room temp. sensor circuit
7. Ambient temp. sensor circuit
8. Vehicle speed signal circuit
9. Front evaporator temp. sensor circuit
10.Front air mix damper position sensor circuit
11. Front air mix damper control servomotor circuit
12.Front air inlet damper position sensor circuit
13.Front air inlet damper control servomotor circuit
14.Condenser
15.Evaporator
16.Heater radiator
17.Expansion valve
18.Integration control and panelAC±23
AC±15
AC±3
AC±96
DI±2336
DI±2319
DI±2322
DI±2370
DI±2325
DI±2346
DI±2355
DI±2349
DI±2358
AC±65
AC±24
AC±35
AC±29
IN±35
Page 2508 of 4323

DI±2306
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2500 Author: Date:
2005 SEQUOIA (RM1146U) Temperature Control: Output air is warmer or cooler than the set
temperature or response is slow
1. Refrigerant volume
2. Drive belt tension
3. Refrigeration system inspection with manifold gauge set
4. Cooling fan system
5. Solar sensor circuit
6. Rear room temp. sensor circuit
7. Ambient temp. sensor circuit
8. Rear evaporator temp. sensor circuit
9. Water valve damper position sensor circuit
10.Water valve damper control servomotor circuit
11. Condenser
12.Evaporator
13.Heater radiator
14.Expansion valve
15.Heater control assembly
16.Integration control and panelAC±23
AC±15
AC±3
AC±96
DI±2336
DI±2333
DI±2322
DI±2330
DI±2352
DI±2361
AC±65
AC±70
AC±45
AC±76
IN±35
IN±35
Temperature Control: No temperature control (only Max. cool or
Max. warm)
1. Rear room temp. sensor circuit
2. Ambient temp. sensor circuit
3. Water valve damper position sensor circuit
4. Water valve damper control servomotor circuit
5. Heater control assembly
6. Integration control and panelDI±2333
DI±2322
DI±2352
DI±2361
IN±35
IN±35
Page 3740 of 4323

I21804
Condition: Periodically cools and then fails to cool
Single A/C:
Dual A/C:
I22613
Condition: Insufficient cooling
Single A/C:
Dual A/C:
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±5
3732 Author: Date:
2005 SEQUOIA (RM1146U)
(2) Moisture present in refrigeration system.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
During operation, pressure on low
pressure side cycles between vac-
uum and normal
Moisture in refrigeration system
freezes at expansion valve orifice
and temporarily stops cycle, but
normal state is restored after the
ice melts Drier in oversaturated state
Moisture in refrigeration system
freezes at expansion valve orifice
and blocks circulation of refriger-
ant(1) Replace receiver
(2) Remove moisture in cycle by
repeatedly evacuating air
(3) Charge proper amount of new
refrigerant
(3) Insufficient cooling
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure low on both low and
high pressure sides
Bubbles seen in sight glass con-
tinuously
Insufficient cooling performance
Gas leakage in refrigeration sys-
tem Insufficient refrigerant in system
Refrigerant leaking
(1) Check for gas leakage with gas
leak detector and repair if neces-
sary
(2) Charge proper amount of re-
frigerant
(3) If indicated pressure value is
near 0 when connected to gauge,
create the vacuum after inspecting
and repairing the location of the
leak
Page 3741 of 4323

I01389
Condition: Insufficient cooling
I01449
Condition: Does not cool (Cools from time to time in some cases) AC±6
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
3733 Author: Date:
2005 SEQUOIA (RM1146U)
(4) Poor circulation of refrigerant
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure low on both low and
high pressure sides
Frost on tube from receiver to
unit
Refrigerant flow obstructed by dirt
in receiverReceiver cloggedReplace receiver
(5) Refrigerant does not circulate
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Vacuum indicated on low pres-
sure side, very low pressure indi-
cated on high pressure side
Frost or dew seen on piping on
both sides of receiver/ drier or ex-
pansion valve Refrigerant flow obstructed by
moisture or dirt in refrigeration sys-
tem
Refrigerant flow obstructed by
gas leakage from expansion valve
Refrigerant does not circulate
(1) Check expansion valve
(2) Clean out dirt in expansion
valve by blowing with air
(3) Replace receiver
(4) Evacuate air and charge new
refrigerant to proper amount
(5) For gas leakage from expan-
sion valve, replace expansion
valve