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Air Conditioning: Diagnosis Lexus GS III

Automatic HVAC System 11 illustrations ~928 words

ON-VEHICLE INSPECTION

  1. INSPECT HOSE AND TUBE CONNECTIONS FOR LOOSENESS
  2. INSPECT HOSES AND TUBES FOR LEAKAGE Using a gas leak detector, check for leakage of refrigerant.

Scheme 140

Scheme 140: COMPONENTS
Scheme 140: COMPONENTS
  1. INSPECT CONDENSER FINS FOR BLOCKAGE OR DAMAGE If the fins are clogged, wash them with water and dry with compressed air. NOTE: Be careful not to damage the fins. If the fins are bent, straighten them with a screwdriver or pliers.
  2. INSPECT CONDENSER AND FITTINGS FOR LEAKAGE OF REFRIGERANT Using a gas leak detector, check for leakage of refrigerant. If there is leakage, check the tightening torque at the joints.

Scheme 141

Scheme 141: COMPONENTS
Scheme 141: COMPONENTS

Scheme 142

Scheme 142: REMOVAL
Scheme 142: REMOVAL

Scheme 143

Scheme 143
Scheme 143

Scheme 144

Scheme 144
Scheme 144
  1. DISCHARGE REFRIGERANT FROM REFRIGERATION SYSTEM HINT: At the time of installation, please refer to the following item. Evacuate air from refrigeration system. Charge system with refrigerant and inspect for leakage of refrigerant. Specified amount : 600 +/- 50 g (21.16 +/- 1.76 oz.)
  2. REMOVE THESE PARTS: Air cleaner duct Air cleaner assembly 2 radiator upper supports
  3. DISCONNECT DISCHARGE HOSE AND LIQUID TUBE Remove the 2 bolts and disconnect the hose and tube. Torque: 10 N.m (100 kgf.cm, 7 ft.lbf) NOTE: Cap the open fittings immediately to keep moisture or dirt out of the system. HINT: At the time of installation, please refer to the following item. Lubricate 2 new O-rings with compressor oil and install them to the hose and tube.
  4. REMOVE CONDENSER Remove the 4 bolts and 2 brackets. Push the radiator toward engine. Push the condenser toward radiator and pull it upward. HINT: At the time of installation, please refer to the following item. If condenser is replaced, add compressor oil to the condenser. Add 40 cc (1.4 fl. oz) Compressor oil: ND - OIL 8 or equivalent

Scheme 145

Scheme 145: REPLACE DRYER FROM MODULATOR
Scheme 145: REPLACE DRYER FROM MODULATOR

Scheme 146

Scheme 146
Scheme 146

Scheme 147

Scheme 147
Scheme 147

Scheme 148

Scheme 148
Scheme 148

Scheme 149

Scheme 149
Scheme 149
  1. Using a hexagon wrench (10 mm, 0.39 in.), remove the cap from the modulator.
  2. Remove the filter from the modulator.
  3. Using pliers, remove the dryer.
  4. Insert a new dryer into the modulator. NOTE: Do not remove the dryer from a vinyl bag until inserting it into the modulator. Install the dryer with its 2 layered part faced upward to the modulator.
  5. Insert the filter into the modulator. NOTE: Install the filter with its protrusion faced downward to the modulator.
  6. Install the cap to the modulator. Apply compressor oil to the o-rings and screw part of the cap. Compressor oil: ND-OIL 8 or equivalent Using a hexagon wrench (10 mm, 0.39 in.), install the caps. Torque: 12.3 N.m (125 kgf.cm, 9 ft.lbf)

INSPECTION

  1. CHECK EVAPORATOR FINS FOR BLOCKAGE If the fins are clogged, clean them with compressed air. NOTE: Never use water to clean the evaporator.
  2. CHECK FITTING FOR CRACKS OR SCRATCHES If necessary, repair or replace.

INSPECT FINS FOR BLOCKAGE

If the fins are clogged, clean them with compressed air.

  1. CHECK QUANTITY OF GAS DURING REFRIGERATION CYCLE
  2. SET ON MANIFOLD GAUGE SET (See «MANIFOLD GAUGE SET»(ref-229445-S01994229252006041500000) )
  3. RUN ENGINE Run the engine at 1,500 RPM for at least 5 minutes. Then check that the high pressure reading is 1.37 - 1.57 MPa (14 - 16 kgf/cm 2 , 199 - 228 psi).
  4. CHECK EXPANSION VALVE If the expansion valve is faulty, the low pressure reading will drop to 0 kPa (0 kgf/cm 2, 0 psi).

Scheme 150

Scheme 150: REMOVAL
Scheme 150: REMOVAL
  1. DISCHARGE REFRIGERANT FROM REFRIGERATION SYSTEM HINT: At the time of installation, please refer to the following item. Evacuate air from refrigeration system. Charge system with refrigerant and inspect for leakage of refrigerant. Specified amount: 600 +/- 50 g (21.16 +/- 1.76 oz.)
  2. REMOVE INSTRUMENT PANEL (See «REMOVAL»(ref-229437-S30123028692006041500000) )
  3. REMOVE EXPANSION VALVE Pry out the packing. HINT: At the in time of installation, please refer to the following item. Do not reuse the packing. Using SST, remove the 4 bolts and separate the expansion valve and tube and accessory. SST 07110-61050 Torque: 4.1 N.m (42 kgf.cm, 36 in.lbf) NOTE: Cap the open fittings immediately to keep moisture or dirt out of the system. HINT: At the in time of installation, please refer to the following item. Lubricate 6 new O-rings with compressor oil and install them to the tube and valve.

INSPECT BLOWER MOTOR CIRCUIT

(See BLOWER MOTOR CIRCUIT )

INSPECT BLOWER MOTOR CONTROL RELAY CIRCUIT

(See BLOWER MOTOR CIRCUIT )

  1. INSPECT AIR INLET DAMPER POSITION SENSOR CIRCUIT (See «DTC B1432/32: AIR INLET DAMPER POSITION SENSOR CIRCUIT, DTC B1442/42 AIR INLET DAMPER POSITION SENSOR CIRCUIT»(ref-229369-S07413105032006041400000) )
  2. INSPECT AIR INLET SERVOMOTOR OPERATION (See «DTC B1442/42: AIR INLET DAMPER CONTROL SERVOMOTOR CIRCUIT»(ref-229369-S42530185922006041400000) )
  3. INSPECT AIR MIX DAMPER POSITION SENSOR CIRCUIT (See «DTC B1431/31: AIR MIX DAMPER POSITION SENSOR CIRCUIT (PASSENGER SIDE) DTC B1441/41 AIR MIX DAMPER POSITION SENSOR CIRCUIT (PASSENGER SIDE)»(ref-229369-S26723415132006041400000) )
  4. INSPECT AIR MIX SERVOMOTOR OPERATION (See «DTC B1441/41: AIR MIX DAMPER CONTROL SERVOMOTOR CIRCUIT (PASSENGER SIDE)»(ref-229369-S14833925142006041400000) )
  5. INSPECT AIR OUTLET DAMPER POSITION SENSOR CIRCUIT (See «DTC B1433/33: AIR OUTLET DAMPER POSITION SENSOR CIRCUIT, DTC B1443/43 AIR OUTLET DAMPER POSITION SENSOR CIRCUIT»(ref-229369-S30170426782006041400000) )
  6. INSPECT AIR OUTLET SERVOMOTOR OPERATION (See «DTC B1443/43: AIR OUTLET DAMPER CONTROL SERVOMOTOR CIRCUIT»(ref-229369-S40087920732006041400000) )
  1. INSPECT SOLAR SENSOR CIRCUIT Driver Side: (See «DTC B1424/24: SOLAR SENSOR CIRCUIT (DRIVER SIDE)»(ref-229369-S01550827762006041400000) ) Passenger Side: (See «DTC B1421/21: SOLAR SENSOR CIRCUIT (PASSENGER SIDE)»(ref-229369-S22191666992006041400000) )
  2. INSPECT ROOM TEMPERATURE SENSOR CIRCUIT (See «DTC B1411/11: ROOM TEMPERATURE SENSOR CIRCUIT»(ref-229369-S41385286662006041400000) )
  3. INSPECT AMBIENT TEMPERATURE SENSOR CIRCUIT (See «DTC B1412/12: AMBIENT TEMPERATURE SENSOR CIRCUIT»(ref-229369-S13989186772006041400000) )
  4. INSPECT EVAPORATOR TEMPERATURE SENSOR (See «DTC B1413/13: EVAPORATOR TEMPERATURE SENSOR CIRCUIT»(ref-229369-S11588658222006041400000) )
  5. INSPECT SMOG VENTILATION SENSOR CIRCUIT (See «DTC B1424/24: SOLAR SENSOR CIRCUIT (DRIVER SIDE)»(ref-229369-S01550827762006041400000) )

INSPECT A/C CONTROL ASSEMBLY CIRCUIT (See TERMINALS OF ECU )

INSPECT A/C AMPLIFIER CIRCUIT

(See TERMINALS OF ECU )

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