engine INFINITI FX35 2005 Service Manual

ATC-96
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
TROUBLE DIAGNOSIS FOR UNUSUAL PRESSURE
Whenever system’s high and/or low side pressure(s) is/are unusual, diagnose using a manifold gauge. The
marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Since the
standard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air tempera-
ture-to-operating pressure table).
Both High- and Low-pressure Sides are Too High
High-pressure Side is Too High and Low-pressure Side is Too Low
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too high. Pressure is reduced soon
after water is splashed on
condenser. Excessive refrigerant charge
in refrigeration cycle. Reduce refrigerant until speci-
fied pressure is obtained.
Air suction by cooling fan is
insufficient. Insufficient condenser cooling
performance.
↓
1. Condenser fins are clogged.
2. Improper fan rotation of cooling fan.

Clean condenser.

Check and repair cooling fan
as necessary.

Low-pressure pipe is not
cold.

When compressor is
stopped high-pressure
value quickly drops by
approximately 196 kPa (2
kg/cm
2 , 28 psi). It then
decreases gradually there-
after. Poor heat exchange in con-
denser
(After compressor operation
stops, high-pressure
decreases too slowly.)
↓
Air in refrigeration cycle. Evacuate repeatedly and
recharge system.
Engine tends to overheat. Engine cooling systems mal-
function. Check and repair each engine
cooling system.

An area of the low-pres-
sure pipe is colder than
areas near the evaporator
outlet.

Plates are sometimes cov-
ered with frost.

Excessive liquid refrigerant
on low-pressure side.

Excessive refrigerant dis-
charge flow.

Expansion valve is open a
little compared with the
specification.
↓
Improper expansion valve
adjustment. Replace expansion valve.
AC359A
Gauge indication Refrigerant cycle Probable cause Corrective action
High-pressure side is too high and
low-pressure side is too low.
Upper side of condenser and
high-pressure side are hot,
however, liquid tank is not so
hot. High-pressure tube or parts
located between compressor
and condenser are clogged or
crushed.

Check and repair or replace
malfunctioning parts.

Check lubricant for contami-
nation.
AC360A

ATC-100
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
Insufficient HeatingAJS00150
SYMPTOM: Insufficient heating
INSPECTION FLOW
*1ATC-61, "Operational Check"*2AT C - 7 3 , "Air Mix Door Motor Circuit"*3ATC-54, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 4 to
6.
*4 ATC-54, "
FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13. *5
AT C - 6 6 , "
LAN System Circuit"*6ATC-79, "Blower Motor Circuit"
*7 EC-208, "DTC P0117, P0118 ECT
SENSOR" (VQ35DE) or EC-914,
"DTC P0117, P0118 ECT SEN-
SOR" (VK45DE) *8
CO-11, "
Changing Engine Coolant"
(VQ35DE) or CO-37, "
Changing
Engine Coolant" (VK45DE) *9
CO-15, "
Checking Radiator Cap"
(VQ35DE) or CO-43, "
Checking
Radiator Cap" (VK45DE)
RJIA2013E

ATC-104
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
Ambient Sensor CircuitAJS00154
COMPONENT DESCRIPTION
Ambient Sensor
The ambient sensor is attached on the hood lock stay. It detects
ambient temperature and converts it into a resistance value which is
then input into the unified meter and A/C amp.
AMBIENT TEMPERATURE INPUT PROCESS
The unified meter and A/C amp. includes a processing circuit for the ambient sensor input. However, when the
temperature detected by the ambient sensor increases quickly, the processing circuit retards the unified meter
and A/C amp. function. It only allows the unified meter and A/C amp. to recognize an ambient temperature
increase of 0.33 °C (0.6 °F) per 100 seconds.
As an example, consider stopping for a few minutes after high speed driving. Although the actual ambient tem-
perature has not changed, the temperature detected by the ambient sensor will increase. This is because the
heat from the engine compartment can radiate to the front grille area, location of the ambient sensor.
DIAGNOSIS PROCEDURE FOR AMBIENT SENSOR
SYMPTOM: Ambient sensor circuit is open or shorted. (21 or −21 is
indicated on unified meter and A/C amp. as a result of performing
self-diagnosis STEP-2.)
1. CHECK VOLTAGE BETWEEN AMBIENT SENSOR AND GROUND
1. Disconnect ambient sensor connector.
2. Turn ignition switch ON.
3. Check voltage between ambient sensor harness connector E34 terminal 1 (Y) and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
RJIA2016E
RJIA1461E
1 – Ground : Approx. 5 V
RJIA2017E

ATC-126
HEATER & COOLING UNIT ASSEMBLY
Revision: 2005 July 2005 FX
HEATER & COOLING UNIT ASSEMBLYPFP:27110
Removal and InstallationAJS0015J
REMOVAL
1. Use a refrigerant collecting equipment (for HFC-134a) to discharge refrigerant.
2. Drain coolant from cooling system. Refer to CO-11, "
Changing Engine Coolant" (VQ35DE) or CO-37,
"Changing Engine Coolant" (VK45DE).
3. Remove cowl top cover. Refer to EI-23, "
COWL TOP" .
4. Remove high-pressure pipe 2 mounting clip.
5. Remove low-pressure flexible hose bracket mounting bolt.
6. Disconnect low-pressure pipe 1 and high-pressure pipe 2 from evaporator.
a. Set a disconnector [High-pressure side (SST: 9253089908), Low-pressure side (SST: 9253089916)] on A/C piping.
b. Slide a disconnector toward vehicle front until it clicks.
c. Slide A/C piping toward vehicle front and disconnect it. CAUTION:
Cap or wrap the joint of the pipe with suitable material such
as vinyl tape to avoid the entry of air.
7. Remove electric throttle control actuator (VQ35DE). Refer to EM-19, "
INTAKE MANIFOLD COLLECTOR" .
8. Disconnect two heater hoses from heater core.
9. Remove instrument panel assembly. Refer to IP-11, "
Removal
and Installation" .
10. Remove blower unit. Refer to ATC-121, "
BLOWER UNIT" .
RJIA2037E
RJIA2041E
RJIA2077E

ATC-128
HEATER & COOLING UNIT ASSEMBLY
Revision: 2005 July 2005 FX

When recharging refrigerant, check for leaks.
NOTE:

When filling radiator with coolant, refer to CO-11, "Changing Engine Coolant" (VQ35DE) or CO-37,
"Changing Engine Coolant" (VK45DE).

Recharge the refrigerant.
Heater & cooling unit mounting bolt
Tightening torque : 6.8 N·m (0.69 kg-m, 60 in-lb)
Steering member mounting nut and bolt
Tightening torque : 12 N·m (1.2 kg-m, 9 fl-lb)

ATC-142
REFRIGERANT LINES
Revision: 2005 July 2005 FX
VK45DE
1. Use a refrigerant collecting equipment (for HFC-134a) to discharge the refrigerant.
2. Remove air cleaner case and air duct. Refer to EM-17, "
AIR CLEANER AND AIR DUCT" (VQ35DE) or
EM-176, "
AIR CLEANER AND AIR DUCT" (VK45DE).
3. Remove front engine undercover, using power tools.
4. Remove cooling fan shroud (lower). Refer to CO-41, "
RADIATOR" (VK45DE).
5. Remove mounting nuts from low-pressure flexible hose and high-pressure flexible hose.
CAUTION:
Cap or wrap the joint of the pipe with suitable material such
as vinyl tape to avoid the entry of air.
6. Remove high-pressure flexible hose. Refer to ATC-149,
"Removal and Installation of High-Pressure Flexible Hose"
(VK45DE).
7. Disconnect compressor connector.
8. Remove A/C compressor belt. Refer to EM-15, "
DRIVE BELTS" (VQ35DE) or EM-173, "DRIVE BELTS"
(VK45DE).
RJIA2244E
RJIA2059E
RJIA2058E

ATC-150
REFRIGERANT LINES
Revision: 2005 July 2005 FX
INSTALLATION
Installation is basically the reverse order of removal.
CAUTION:

Replace O-rings of high-pressure flexible hose with new ones, and then apply compressor oil to it
when installing it.

Connection point for female-side piping is thin. So, when inserting male-side piping, take care not
to deform female-side piping. Slowly insert in axial direction.

Insert one-touch joint connection point securely until it clicks.

After piping has been connected, pull male-side piping by hand to make sure piping does not
come off.

When recharging refrigerant, check for leaks.
Removal and Installation of Low-Pressure Pipe 1 (Engine Compartment)AJS0015V
REMOVAL
1. Use a refrigerant collecting equipment (for HFC-134a) to discharge the refrigerant.
2. Remove cowl top cover. Refer to EI-23, "
COWL TOP" .
3. Remove mounting bolt from low-pressure pipe 1 bracket and low-pressure flexible hose bracket.
4. Disconnect one-touch joints.
a. Set a disconnector (SST: 9253089916) on A/C piping.
b. Slide a disconnector toward vehicle front until it clicks.
c. Slide A/C piping toward vehicle front and disconnect it.
RJIA2067E
High-pressure flexible hose bracket mounting bolt
Tightening torque : 5.5 N·m (0.56 kg-m, 49 in-lb)
RJIA2068E
RJIA2069E

REFRIGERANT LINES ATC-151
C
D E
F
G H
I
K L
M A
B
AT C
Revision: 2005 July 2005 FX
5. Remove low-pressure pipe 1.
CAUTION:
Cap or wrap the joint of the pipe with suitable material such
as vinyl tape to avoid the entry of air.
INSTALLATION
Installation is basically the reverse order of removal.
CAUTION:

Replace O-rings of low-pressure pipe 1 with new ones, and then apply compressor oil to it when
installing it.

Connection point for female-side piping is thin. So, when inserting male-side piping, take care not
to deform female-side piping. Slowly insert in axial direction.

Insert one-touch joint connection point securely until it clicks.

After piping has been connected, pull male-side piping by hand to make sure piping does not
come off.

When recharging refrigerant, check for leaks.
Removal and Installation of High-Pressure Pipe 1 and 2 (Engine Compartment)AJS001BH
REMOVAL
1. Remove low-pressure pipe 1. Refer to ATC-150, "Removal and Installation of Low-Pressure Pipe 1
(Engine Compartment)" .
2. Remove high-pressure flexible hose and low-pressure flexible hose. Refer to ATC-149, "
Removal and
Installation of High-Pressure Flexible Hose" and ATC-148, "Removal and Installation of Low-Pressure
Flexible Hose" .
3. Remove high-pressure pipe 1 and 2 from clips.
4. Disconnect one-touch joint between condenser and high-pres- sure pipe 1.
a. Set a disconnector (SST: 9253089908) on A/C piping.
b. Slide a disconnector upward until it clicks.
c. Slide A/C piping upward and disconnect it.
CAUTION:
Cap or wrap the joint of the pipe with suitable material such
as vinyl tape to avoid the entry of air.
RJIA2037E
Low-pressure pipe 1 bracket and low-pressure flexible hose bracket mounting bolts
Tightening torque : 5.5 N·m (0.56 kg-m, 49 in-lb)
RJIA2070E
RJIA2071E

REFRIGERANT LINES ATC-155
C
D E
F
G H
I
K L
M A
B
AT C
Revision: 2005 July 2005 FX
Removal and Installation of CondenserAJS0015Z
REMOVAL
1. Use a refrigerant collecting equipment (for HFC-134a) to discharge the refrigerant.
2. Remove the air cleaner case and air duct. Refer to EM-17, "
AIR CLEANER AND AIR DUCT" (VQ35DE)
or EM-176, "
AIR CLEANER AND AIR DUCT" (VK45DE).
3. Remove engine undercover, using power tools.
4. Drain engine coolant (VK45DE). Refer to CO-37, "
Changing Engine Coolant" .
5. Remove cooling fan shroud after removing radiator upper hose (VK45DE). Refer to CO-41, "
RADIATOR" .
6. Remove mounting bolt for high-pressure flexible hose bracket.
7. Disconnect high-pressure flexible hose and high-pressure pipe 1 from condenser.
a. Set a disconnector [condenser outlet (SST: 9253089908), con- denser inlet (SST: 9253089912)]on A/C piping.
b. Slide a disconnector upward until it clicks.
c. Slide A/C piping upward and disconnect it.
CAUTION:
Cap or wrap the joint of the pipe with suitable material such
as vinyl tape to avoid the entry of air.
8. Remove mounting bolts for condenser.
9. Remove radiator upper mount, move radiator and condenser to the engine side.
10. Remove condenser. CAUTION:
Be careful not to damage the core surface of the condenser and the radiator.
INSTALLATION
Installation is basically the reverse order of removal.
CAUTION:

Replace O-rings of A/C piping with new ones, and then apply compressor oil to it when installing
it.

Connection point for female-side piping is thin. So, when inserting male-side piping, take care not
to deform female-side piping. Slowly insert in axial direction.

Insert one-touch joint connection point securely until it clicks.
RJIA2065E
RJIA2066E
RJIA2075E

ATC-158
REFRIGERANT LINES
Revision: 2005 July 2005 FX
Checking for Refrigerant LeaksAJS00163
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 electronic refrigerant leak detector or fluorescent
dye leak detector (SST: J-42220).
If dye is observed, confirm the leak with an electronic refrigerant leak detector. It is possible a prior leak was
repaired and not properly cleaned.
When searching for leaks, do not stop when one leak is found but continue to check for additional leaks at all
system components and connections.
When searching for refrigerant leaks using an electronic leak detector, move the probe along the suspected
leak area at 1 to 2 inches per second and no further than 1/4 inch from the component.
CAUTION:
Moving the electronic leak detector probe slower and closer to the suspected leak area will improve
the chances of finding a leak.
Checking System for Leaks Using the Fluorescent Leak DetectorAJS00164
1. Check A/C system for leaks using the UV lamp and safety goggles (SST: J42220) in a low sunlight area (area without windows preferable). Illuminate all components, fittings and lines. The dye will appear 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) leak.
2. If the suspected area is difficult to see, use an adjustable mirror or wipe the area with a clean shop rag or cloth, with the UV lamp for dye residue.
3. After the leak is repaired, remove any residual dye using dye cleaner (SST: J43872) to prevent future mis- diagnosis.
4. Perform a system performance check and verify the leak repair with an approved electronic refrigerant leak detector.
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 can also cause false readings
and may damage the detector.
Dye InjectionAJS00165
(This procedure is only necessary when recharging the system or when the compressor has seized and was
replaced.)
1. Check A/C system static (at rest) pressure. Pressure must be at least 345 kPa (3.52 kg/cm
2 , 50 psi).
2. Pour one bottle (1/4 ounce / 7.4 cc) of the A/C refrigerant dye into the injector tool (SST: J 41459).
3. Connect the injector tool to the A/C Low-pressure side service fitting.
4. Start engine and switch A/C ON.
5. When the A/C operating (compressor running), 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).
6. With the engine still running, disconnect the injector tool from the service fitting. CAUTION:
Be careful the A/C system or replacing a component, pour the dye directly into the open system
connection and proceed with the service procedures.
7. Operate the A/C system for a minimum of 20 minutes to mix the dye with the system oil. Depending on the leak size, operating conditions and location of the leak, it may take from minutes to days for the dye to
penetrate a leak and become visible.
8. Attach a blue label as necessary.