Infiniti G37 Coupe. Manual - part 746

HA-30

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REFRIGERATION SYSTEM

Ambient Air Temperature-to-operating Pressure Table

Refrigerant Leakages

INFOID:0000000001675629

Perform a visual inspection of all refrigeration parts, fittings, hoses and components for signs of A/C lubricant
leakage, damage and corrosion. A/C lubricant leakage may indicate an area of refrigerant leakage. Allow
extra inspection time in these areas when using either an electrical leak detector or fluorescent dye leak
detector (SST: J-42220).
Confirm the leakage with an electrical leak detector if dye is observed. It is possible a prior leakage was
repaired and not properly cleaned.
Do not stop when one leakage is found but continue checking for additional leakages at all system compo-
nents and connections when searching for leakages.
Move the probe along the suspected leakage area at 1 to 2 inches per second and no further than 1/4 inch
from the component when searching for refrigerant leakages using an electrical leak detector.

CAUTION:

Moving the electrical leak detector probe slower and closer to the suspected leakage area improves
the chances of finding a leakage.

60 - 70

20 (68)

7.9 - 9.4 (46 - 49)

25 (77)

12.8 - 14.9 (55 - 59)

30 (86)

17.6 - 20.3 (64 - 69)

35 (95)

22.3 - 25.7 (72 - 78)

Ambient air

High-pressure (Discharge side)

kPa (kg/cm

, psi)

Low-pressure (Suction side)

kPa (kg/cm

, psi)

Relative humidity

Air temperature

C (

50 - 70

20 (68)

768 - 940

(7.8 - 9.6, 111.4 - 136.3)

180 - 220

(1.8 - 2.2, 26.1 - 31.9)

25 (77)

925 - 1,131

(9.4 - 11.5, 134.1 - 164.0)

218 - 267

(2.2 - 2.7, 31.6 - 38.7)

30 (86)

1,082 - 1,322

(11.0 - 13.5, 156.9 - 191.7)

258 - 314

(2.6 - 3.2, 37.4 - 45.5)

35 (95)

1,238 - 1,513

(12.6 - 15.4, 179.5 - 219.4)

296 - 362

(3.0 - 3.7, 42.9 - 52.5)

40 (104)

1,395 - 1,704

(14.2 - 17.4, 202.3 - 247.1)

335 - 408

(3.4 - 4.2, 48.6 - 59.2)

Inside air (Recirculating air) at blower assembly inlet

Discharge air temperature at center ventilator

C (

Relative humidity

Air temperature

C (

FLUORESCENT LEAK DETECTOR

HA-31

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FLUORESCENT LEAK DETECTOR

Inspection

INFOID:0000000001675630

CHECKING SYSTEM FOR LEAKAGES USING THE FLUORESCENT LEAK DETECTOR

Check A/C system for leakages using the UV lamp and safety goggles (SST: J-42220) in a low sunlight
area (area without windows preferable). Illuminate all components, fittings and lines. The dye appears as
a bright green/yellow area at the point of leakage. Fluorescent dye observed at the evaporator drain open-
ing indicates an evaporator core assembly (tubes, core or expansion valve) leakage.

Use an adjustable mirror or wipe the area with a clean shop rag or cloth, with the UV lamp for dye residue
if the suspected area is difficult to see.

Remove any residual dye using dye cleaner (SST: J-43872) to prevent future misdiagnosis after the leak-
age is repaired.

Perform a system performance check and verify the leakage repair with an approved electrical leak detec-
tor.

NOTE:
Other gases in the work area or substances on the A/C components, for example, anti-freeze, windshield
washer fluid, solvents and lubricants, may falsely trigger the leak detector. Make sure the surfaces to be
checked are clean.
Clean with a dry cloth or blow off with shop air.
Do not allow the sensor tip of the detector to contact with any substance. This may also cause false readings
and may damage the detector.

DYE INJECTION

(This procedure is only necessary when recharging the system or when the compressor has seized and was
replaced.)

Check A/C system static (at rest) pressure. Pressure must be at least 345 kPa (3.52 kg/cm

, 50 psi).

Pour one bottle (1/4 ounce / 7.4 cc) of the A/C refrigerant dye into the injector tool (SST: J-41459).

Connect the injector tool to the A/C low-pressure side service valve.

Start the engine. Then switch A/C ON.

Inject one bottle (1/4 ounce / 7.4 cc) of fluorescent dye through the low-pressure service valve using dye
injector tool (SST: J-41459) (refer to the manufacture’s operating instructions) when the A/C operating
(compressor running).

Disconnect the injector tool from the service valve with the engine still running.

CAUTION:

Be careful when replacing the A/C system or a component, pour the dye directly into the open sys-
tem connection and proceed with the service procedures.

Operate the A/C system for a minimum of 20 minutes to mix the dye with the system oil. Depending on the
leakage size, operating conditions and location of the leakage, it may take from minutes to days for the
dye to penetrate a leakage and become visible.

Attach a blue label if necessary.

HA-32

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ELECTRICAL LEAK DETECTOR

ELECTRICAL LEAK DETECTOR

Inspection

INFOID:0000000001675631

PRECAUTIONS FOR HANDLING LEAK DETECTOR

Use an electrical leak detector (SST: J-41995) or equivalent when
performing a refrigerant leakage check. Ensure that the instrument is
calibrated and set properly per the operating instructions.
The leak detector is a delicate device. Read the operating instruc-
tions and perform any specified maintenance for using the leak
detector properly.

Position probe approximately 5 mm (3/16 in) away from point to
be checked.

Circle each fitting completely with probe when testing.

Move probe along component approximately 25 to 50 mm (1 to
2 in)/sec.

CHECKING PROCEDURE

Check that there is no refrigerant vapor, shop chemicals, or cigarette smoke in the vicinity of the vehicle to pre-
vent inaccurate or false readings. Perform the leakage test in calm area (low air/wind movement) so that the
leaking refrigerant is not dispersed.

Stop the engine.

AHA281A

SHA707EA

SHA706E

SHA708EA

ELECTRICAL LEAK DETECTOR

HA-33

< ON-VEHICLE MAINTENANCE >

Connect a suitable A/C manifold gauge set (SST: J-39183) to the A/C service valves.

Check if the A/C refrigerant pressure is at least 345 kPa (3.52 kg/cm

, 50 psi) above 16

C (61

F).

Recover/evacuate and recharge the system with the specified amount of refrigerant if less than specifica-
tion.
NOTE:
Leakages may not be detected since the system may not reach 345 kPa (3.52 kg/cm

, 50 psi) at temper-

atures below 16

C (61

F).

Perform the leakage test from the high-pressure side (compressor discharge a to evaporator inlet j) to the
low-pressure side (evaporator drain hose k to shaft seal p). Perform a leakage check for the following
areas carefully. Clean the component to be checked and move the leakage detected probe completely
around the connection/component.

Compressor
Check the fitting of high- and low-pressure flexible hoses, relief valve and shaft seal.
Condenser
Check the fitting of condenser pipe assembly, high-pressure flexible hose and pipe.
Liquid tank
Check the fitting of radiator & condenser assembly and refrigerant pressure sensor.
Service valves
Check all around the service valves. Ensure service valve caps are secured on the service valves (to pre-
vent leakages).
NOTE:
Wipe any residue from valves to prevent any false readings by leak detector after removing A/C manifold
gauge set from service valves.
Cooling unit (Evaporator)
Turn blower fan on “High” for at least 15 seconds to dissipate any refrigerant trace in the cooling unit with
engine OFF. Wait a minimum of 10 minutes accumulation time (refer to the manufacturer’s recommended
procedure for actual wait time) before inserting the leak detector probe into the drain hose.
Keep the probe inserted for at least 10 seconds. Use caution not to contaminate the probe tip with water
or dirt that may be in the drain hose.

JSIIA0010GB

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