Wrong Okay

Coloriage Trains

G02928521

Fig. 3: Identifying Compressor Operation Condition

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

9. SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

The SEQUOIA is equipped with an SRS (Supplemental Restraint System) such as the driver, passenger, side, curtain shield airbag. Failure to carry out service operation in the correct sequence could cause the SRS to unexpectedly deploy during servicing, possibly leading to a serious accident. Before servicing (including removal or installation of parts, inspection or replacement), be sure to read the precautionary notices TN the RS section.

ON-VEHICLE INSPECTION

1. INSPECT REFRIGERANT VOLUME

Observe the sight glass on the liquid tube. Test conditions:

• Running engine at 1,500 RPM

• Front blower speed control dial at "HI" position

Front and rear blower speed set at "HI" position

Front temperature control dial at "MAX. COOL" position

Front temperature control dial at "MAX. COOL" position Rear temperature control set at 18.5 °C (65°F)

• Fully open the doors

2004 HVAC Air Conditioning System - Sequoia

Toyota Tacoma Receiver Drier

G02928522

Fig. 4: Identifying Slight Glass On Liquid Tube Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Item

Symptom

Amount of refrigerant

Remedy

1

Bubbles present In sight glass continuously

Insufficient*

(1) Check for gas leakage with gas leak detector and repair if necessary

(2) Add refrigerant until continuous bubble presence stops disappear

2

No bubbles present in sight glass

None, sufficient or too much

Refer item 3 and 4

3

No temperature difference between compressor inlet and outlet

Empty or nearly empty

(1) Check for gas leakage with gas leak detector and repair if necessary

(2) Add refrigerant until bubbles disappear

4

Temperature between compressor inlet and outlet is noticeably different

Correct or too much

Refer to items 5 and 6

5

Immediately after air conditioning is turned oft, refrigerant in sight glass stays clear

Too much

(1) Discharge refrigerant

(2) Evacuate air and charge proper amount or purified refrigerant

6

When air conditioning is turned of, refrigerant foams and then stays clear

Correct

*: Bubbles in the sight glass with ambient temperatures higher than usual can be considered normal if cooling is sufficient.

Fig. 5: Problem Symptom Table

2004 HVAC Air Conditioning System - Sequoia

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

This is a method for checking the A/C system by using a manifold gauge set. Read the manifold gauge pressure when the conditions below are met.

Test conditions:

• Temperature at the air inlet with R/F switch set at RECIRC is 30-35 °C (86-95 °F)

• Engine running at 1500 RPM

• Blower speed control switch at "HI" position

• Temperature control dial at "MAX. COOL" position

Rear temperature control set at 18.5°C (65°F)

NOTE: It should be noted that the gauge indications may vary slightly due to ambient temperature conditions.

1. Normally functioning refrigeration system. Gauge reading:

Single A/C:

REFRIGERATION SYSTEM GAUGE READING

Gauge

MPa

kgf°Cm2

Low pressure

0.15-0.25

1.5-2.5

High Pressure

1.6-1.8

REFRIGERATION SYSTEM GAUGE READING

Gauge

MPa

kgf°Cm2

Low pressure

0.25-0.35

2.5-3.5

High Pressure

1.9-2.1

19-21

2004 HVAC Air Conditioning System - Sequoia

Fig. 6: Inspecting Refrigerant Pressure With Manifold Gauge Set (Normally Functioning) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2. Moisture present in refrigeration system.

Monochoriaal Diamniotische Tweeling
Fig. 7: Inspecting Refrigerant Pressure With Manifold Gauge Set (Moisture Present) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Symptom seen in refrigeration system

Probable cause

Diagnosis

Remedy

During operation, pressure on low pressure side sometimes become a vacuum and sometime normal

Moisture entered in refrigeration system freezes at expansion valve orifice and temporarily stops cycle, but normal state is restored after a time when the ice melts

• Drier in over satura ted slate

• Moisture in refrigeration system freezes at expansion valve orifice and blocks circulation of refrigerant

(1) Replace receiver

(2) Remove moisture in cycle through repeatedly evacuating air

(3) Charge proper amount of new refrigerant

Fig. 8: Problem Symptom Table (Moisture Present)

2004 HVAC Air Conditioning System - Sequoia

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

3. Insufficient cooling

Condition: Insufficient cooling

G0292BS27

Fig. 9: Inspecting Refrigerant Pressure With Manifold Gauge Set (Insufficient Cooling) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Symptom seen in refrigeration system

Probable cause

Diagnosis

Remedy

• Pressure low on both low and high pressure sides

- Bubbles seen in sight glass continuously

• Insufficient cooling performance

Gas leakage at some place in refrigeration system

• Insufficient refrigerant in system

• Refrigerant leaking

(1) Check for gas leakage with gas leak detcctor and repair if nocos saiy

(?) Charge proper amount of refrigerant

(3) If indicated pressure value is near 0 when connected lo gauge, create the vacuum after inspecting and repairing the location of the leak

G02SZB52S

G02SZB52S

Fig. 10: Problem Symptom Table (Insufficient Cooling) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

4. Poor circulation of refrigerant

2004 HVAC Air Conditioning System - Sequoia

Condition: Insufficient cooling

Fig. 11: Inspecting Refrigerant Pressure With Manifold Gauge Set (Poor Circulation) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

G02928529

Fig. 11: Inspecting Refrigerant Pressure With Manifold Gauge Set (Poor Circulation) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Symptom seen in refrigeration system

Probable cause

Diagnosis

Remedy

■ Pressure tow in both low and high pressure sides - Frost on tube from receiver 1o unit

Refrigerant flow obstructed by dir! in receiver

Receiver clogged

Replace rocciver

G 0252653*]

G 0252653*]

Fig. 12: Problem Symptom Table (Poor Circulation) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

5. Refrigerant does not circulate

Condition: Does not cool (Cools from time to time in some cases)

Fig. 13: Inspecting Refrigerant Pressure With Manifold Gauge Set (Refrigerant Doesn't

G02928531

Fig. 13: Inspecting Refrigerant Pressure With Manifold Gauge Set (Refrigerant Doesn't

2004 HVAC Air Conditioning System - Sequoia

Circulate)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Symptom seen in refrigeration system

Probable cause

Diagnosis

Remedy

• Vacuum indicated on low pressure side, very low pressure indicated on high pressure side

• Trost or dew seen on piping before and after receiver/ drier or expansion valve

• Refrigerant flow obstructed by moisture or dirt in refrigeration system

• 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 refngerant to proper amount

(5) For gas leakage from expansion valve, replace expansion valve

G0M28S32

G0M28S32

Fig. 14: Problem Symptom Table (Refrigerant Doesn't Circulate) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

6. Refrigerant overcharged or insufficient cooling of condenser

Condition: Insufficient cooling Single

G02928533

Fig. 15: Inspecting Refrigerant Pressure With Manifold Gauge Set (Refrigerant Overcharged Of Condenser)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Symptom seen in refrigeration system

Probable cause

Diagnosis

Remedy

• Pressure too high on both low and high pressure sides

• No air bubbles seen through the sight glass even when the engine rpm is lowered

» Unable to develop sufficient performance due to excessive • Insufficient cooling of condenser

• Excessive refrigerant in cycle—»refrigerant overcharged

• Condenser cooling insufficienMcondenser fins clogged of cooling fan faulty

(1) Clean condenser

(2) Check cooling fan with fluid coupling operation

(3) If (1) and (2) are In normal state, check amount of refrigerant Charge proper amount of rcfrigor ant

G02S2B534

G02S2B534

Condenser Overcharging

Fig. 15: Inspecting Refrigerant Pressure With Manifold Gauge Set (Refrigerant Overcharged Of Condenser)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2004 HVAC Air Conditioning System - Sequoia

Fig. 16: Problem Symptom Table (Refrigerant Overcharged Of Condenser) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

7. Air present in refrigeration system

Condition: Insufficient cooling

Single A/C: Dual A/C

eration system has been opens and the refrigerant charged without vacuum N purging.

G02928535

eration system has been opens and the refrigerant charged without vacuum N purging.

G02928535

Fig. 17: Inspecting Refrigerant Pressure With Manifold Gauge Set (Air Present) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Symptom seen in refrigeration system

Probable cause

Diagnosis

Remedy

• Pressure loo high on both tow and high pressure sides

■ The low pressure piping hot to Ihe touch

• Bubbles seen in sight glass

Air entered in refrigeration system

• Air present in refrigeration system

• Insufficient vacuum purging

(1) Check compressor oil to see it it is see if it is dirty or insufficient

(2) Evacuate air and charge new refrigerant

G 02S28S3«

G 02S28S3«

Fig. 18: Problem Symptom Table (Air Present) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

8. Expansion valve improperly

2004 HVAC Air Conditioning System - Sequoia

Fig. 19: Inspecting Refrigerant Pressure With Manifold Gauge Set (Expansion Valve Improperly)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Fig. 19: Inspecting Refrigerant Pressure With Manifold Gauge Set (Expansion Valve Improperly)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Symptom seen in refngeration system

Probable cause

Diagnosis

Remedy

• Pressure too high on both low and high pressure sides

• Frost or large amount of dew on piping on low pressure side

Trouble in expansion valve

• Excessive refrigerant in low pressure piping

• Expansion valve opened too wide

Check expansion valve Replace if defective

Fig. 20: Problem Symptom Table (Expansion Valve Improperly) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

9. Defective compression compressor

Chorion Tweeling
Fig. 21: Inspecting Refrigerant Pressure With Manifold Gauge Set (Defective Compression Compressor)

2004 HVAC Air Conditioning System - Sequoia

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Symptom seen in refrigeration system

Probable cause

Diagnosis

Remedy

• Pressure too high on low nigh pressure sides

• Pressure too low to on high pros sure side

Internal leak in compressor

■ Compression defective • Valve leaking or broken s iding parts

Repair or replace compressor

G 029285«

G 029285«

Fig. 22: Problem Symptom Table (Defective Compression Compressor) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

3. INSPECT IDLE-UP SPEED

a. Warm up engine.

b. Inspect idle-up speed when the these conditions are established.

• Blower speed control switch at "HI" position

• Temperature control dial at "COOL" position

MAGNETIC CLUTCH CONDITION IDLE-UP SPEED

Magnetic clutch condition

Idle-up speed

Magnetic clutch not engaged

700 +/- 50 rpm

Magnetic clutch engaged

780 +/- 50 rpm

If idle speed is not as specified, check Idle control system. 4. INSPECT FOR LEAKAGE OF REFRIGERANT

a. Perform in these conditions:

• 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.)

• Make sure that there is some refrigerant remaining in the refrigeration system. When compressor is OFF: approx. 392-588 kPa (4-6 kgf/ cm2 , 57-85 psi)

b. Bring the gas leak detector close to the drain hose before performing the test.

NOTE: • After the blower motor stopped, leave the cooling unit for more than

15 minutes.

2004 HVAC Air Conditioning System - Sequoia

• 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 motor linear controller 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.

EVACUATING

1. CONNECT QUICK DISCONNECT ADAPTER TO CHARGING HOSES

2. REMOVE CAPS FROM SERVICE VALVES ON REFRIGERANT LINES

3. SET ON MANIFOLD GAUGE SET

a. Close both hand valves of manifold gauge set.

b. Connect the quick disconnect adapters to the service valves.

2004 HVAC Air Conditioning System - Sequoia

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