TROUBLE DIAGNOSIS
ATC-63
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Revision: 2004 November 2004 FX35/FX45
CHECKING AUTO MODE
1. Press AUTO switch and A/C switch.
2. Display should indicate AUTO.
Confirm that the compressor clutch engages (sound or visual
inspection). (Discharge air and blower speed will depend on
ambient, in-vehicle, and set temperatures.)
If NG, go to trouble diagnosis procedure for AT C - 6 3 , "
Power Supply
and Ground Circuit for Auto Amp." , then if necessary, trouble diag-
nosis procedure for AT C - 8 4 , "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go
to malfunction Simulation Tests in GI-27, "
How to Perform Efficient
Diagnosis for an Electrical Incident" and perform tests as outlined to
simulate driving conditions environment. If symptom appears, refer
to AT C - 4 2 , "
SYMPTOM TABLE" and perform applicable trouble diagnosis procedures.
Power Supply and Ground Circuit for Auto Amp.AJS001BF
SYMPTOM: A/C system does not come on.
INSPECTION FLOW
RJIA1979E
*1AT C - 6 4 , "DIAGNOSTIC PROCE-
DURE FOR A/C SYSTEM".*2ATC-61, "
Operational Check".*3AV- 7 8 , "Trouble Diagnosis Chart by
Symptom".
*4AV- 8 4 , "
A/C and AV Switch Does Not
Operate".
RJIA1980E
TROUBLE DIAGNOSIS
ATC-87
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AT C
Revision: 2004 November 2004 FX35/FX45
5. CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer to AT C - 4 0 , "
CONSULT-II" .
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6. CHECK CIRCUIT CONTINUITY BETWEEN BCM AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and unified meter and A/C amp.
connector.
3. Check continuity between BCM harness connector M3 terminal
27 (R/Y) and unified meter and A/C amp. harness connector
M57 terminal 42 (R/Y).
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector.
7. CHECK VOLTAGE FOR UNIFIED METER AND A/C AMP. (COMPRESSOR ON SIGNAL)
1. Reconnect BCM connector and unified meter and A/C amp.
connector.
2. Turn ignition switch ON.
3. Check voltage between unified meter and A/C amp. harness
connector M57 terminal 42 (R/Y) and ground.
OK or NG
OK >> GO TO 8.
NG-1 >> If the voltage is approx. 5V when A/C switch is ON: Replace unified meter and A/C amp.
NG-2 >> If the voltage is approx. 0V when A/C switch is OFF: Replace BCM.A/C SW ON : AIR COND SW ON
A/C SW OFF : AIR COND SW OFF
R J I A 1111 E
27 – 42 : Continuity should exist.
RJIA2006E
Terminals
Condition Voltage (+)
(−) Unified meter
and A/C amp.
connectorTerminal No.
(wire color)
M57 42 (R/Y) GroundA/C switch: ON Approx. 0V
A/C switch: OFF Approx. 5V
RJIA2007E
ATC-88
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
8. CHECK REFRIGERANT PRESSURE SENSOR
WITH CONSULT-II
1. Start the engine.
2. Check voltage of refrigerant pressure sensor. Refer to EC-125, "
CONSULT-II Reference Value in Data
Monitor" (VQ35DE) or EC-775, "CONSULT-II Reference Value in Data Monitor" (VK45DE).
WITHOUT CONSULT-II
1. Start the engine.
2. Check voltage between ECM harness connector F101 terminal
70 (L/R) and ground.
OK or NG
OK >>WITH CONSULT-II
GO TO 9.
WITHOUT CONSULT-II
GO TO 10.
NG >> Refer to EC-609, "
REFRIGERANT PRESSURE SENSOR" (VQ35DE) or EC-1287, "REFRIGER-
ANT PRESSURE SENSOR" (VK45DE).
9. CHECK BCM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer to AT C - 4 0 , "
CONSULT-II" .
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
10. CHECK CIRCUIT CONTINUITY BETWEEN BCM AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and unified meter and A/C amp.
connector.
3. Check continuity between BCM harness connector M3 terminal
28 (BR/Y) and unified meter and A/C amp. harness connector
M57 terminal 57 (BR/Y).
OK or NG
OK >> GO TO 11.
NG >> Repair harness or connector.
Te r m i n a l s
Condition Voltage (+)
(−)
ECM con-
nectorTerminal No.
(wire color)
F101 70 (L/R) Ground A/C switch: ON Approx. 1 - 4V
PBIB1188E
FAN SW ON :FAN ON SIG ON
FAN SW OFF :FAN ON SIG OFF
R J I A 1111 E
28 – 57 : Continuity should exist.
RJIA2009E
TROUBLE DIAGNOSIS
ATC-89
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AT C
Revision: 2004 November 2004 FX35/FX45
11 . CHECK VOLTAGE FOR UNIFIED METER AND A/C AMP. (FAN ON SIGNAL)
1. Reconnect BCM connector and unified meter and A/C amp.
connector.
2. Turn ignition switch ON.
3. Check voltage between unified meter and A/C amp. harness
connector M57 terminal 57 (BR/Y) and ground.
OK or NG
OK >> GO TO 12.
NG-1 >> If the voltage is approx. 5V when blower motor is ON: Replace unified meter and A/C amp.
NG-2 >> If the voltage is approx. 0V when blower motor is OFF: Replace BCM. Refer to BCS-15, "
Removal
and Installation of BCM" .
12. CHECK CAN COMMUNICATION
Check CAN communication. Refer to BCS-14, "
CAN Communication Inspection Using CONSULT-II (Self-
Diagnosis)" .
BCM – ECM
ECM – IPDM E/R
ECM – Unified meter and A/C amp.
OK or NG
OK >> INSPECTION END
NG >> Repair or replace malfunctioning part(s).
Terminals
Condition Voltage (+)
(-) Unified meter
and A/C amp.
connectorTerminal No.
(wire color)
M57 57 (BR/Y) GroundA/C switch: ON
(Blower motor
operates)Approx. 0V
OFF switch: ON
(A/C system:
OFF)Approx. 5V
RJIA2010E
TROUBLE DIAGNOSIS
ATC-95
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Revision: 2004 November 2004 FX35/FX45
PERFORMANCE CHART
Test Condition
Testing must be performed as follows:
Test Reading
Recirculating-to-discharge Air Temperature Table
Ambient Air Temperature-to-operating Pressure Table
Vehicle location Indoors or in the shade (in a well-ventilated place)
Doors Closed
Door window Open
Hood Open
TEMP. Max. COLD
Mode switch
(Ventilation) set
Recirculation (REC) switch
(Recirculation) set
Fan (blower) speedMax. speed set
Engine speed Idle speed
Operate the air conditioning system for 10 minutes before taking measurements.
Inside air (Recirculating air) at blower assembly inlet
Discharge air temperature at center ventilator
°C (°F) Relative humidity
%Air temperature
°C (°F)
50 - 6020 (68) 11.2 - 13.2 (52 - 56)
25 (77) 12.2 - 14.8 (54 - 59)
30 (86) 15.5 - 18.6 (60 - 65)
35 (95) 21.0 - 24.5 (70 - 76)
40 (104) 28.7 - 32.6 (84 - 91)
60 - 7020 (68) 13.2 - 15.2 (56 - 59)
25 (77) 14.8 - 17.3 (59 - 63)
30 (86) 18.6 - 21.6 (65 - 71)
35 (95) 24.5 - 28.0 (76 - 82)
40 (104) 32.6 - 36.5 (91 - 98)
Ambient air
High-pressure (Discharge side)
kPa (kg/cm
2 , psi)Low-pressure (Suction side)
kPa (kg/cm2 , psi) Relative humidity
%Air temperature
°C (°F)
50 - 7020 (68)961 - 1,167
(9.8 - 11.9, 139 - 169)216 - 265
(2.2 - 2.7, 31 - 38)
25 (77)1,108 - 1,353
(11.3 - 13.8, 161 - 196)230 - 281
(2.3 - 2.9, 33 - 41)
30 (86)1,275 - 1,549
(13.0 - 15.8, 185 - 225)261 - 320
(2.7 - 3.3, 38 - 46)
35 (95)1,549 - 1,893
(15.8 - 19.3, 225 - 274)297 - 364
(3.0 - 3.7, 43 - 53)
40 (104)1,814 - 2,216
(18.5 - 22.6, 263 - 321)357 - 435
(3.6 - 4.4, 52 - 63)
ATC-98
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
Low-pressure Side Sometimes Becomes Negative
Low-pressure Side Becomes Negative
DIAGNOSTIC PROCEDURE FOR INSUFFICIENT COOLING
SYMPTOM: Insufficient cooling
1. CHECK POWER SUPPLY FOR ECV (ELECTRONIC CONTROL VALVE)
1. Disconnect compressor (ECV) connector.
2. Turn ignition switch ON.
3. Check voltage between compressor harness connector F6 ter-
minal 2 (G) and ground.
OK or NG
OK >> GO TO 2.
NG >> Check power supply circuit and 10A fuse [No. 12,
located in the fuse block (J/B)]. Refer to PG-83, "
FUSE
BLOCK - JUNCTION BOX (J/B)" .
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side sometimes
becomes negative.
Air conditioning system
does not function and does
not cyclically cool the com-
partment air.
The system constantly func-
tions for a certain period of
time after compressor is
stopped and restarted.Refrigerant does not dis-
charge cyclically.
↓
Moisture is frozen at expan-
sion valve outlet and inlet.
↓
Water is mixed with refriger-
ant.
Drain water from refrigerant
or replace refrigerant.
Replace liquid tank.
AC354A
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side becomes nega-
tive.
Liquid tank or front/rear side of
expansion valve′s pipe is
frosted or dewed.High-pressure side is closed
and refrigerant does not flow.
↓
Expansion valve or liquid tank
is frosted.Leave the system at rest until
no frost is present. Start it
again to check whether or not
the malfunction is caused by
water or foreign particles.
If water is the cause, initially
cooling is okay. Then the
water freezes causing a
blockage. Drain water from
refrigerant or replace refrig-
erant.
If due to foreign particles,
remove expansion valve
and remove the particles
with dry and compressed air
(not shop air).
If either of the above meth-
ods cannot correct the mal-
function, replace expansion
valve.
Replace liquid tank.
Check lubricant for contami-
nation.
AC362A
2 – ground : Battery voltage
RJIA2294E
REFRIGERANT LINES
ATC-157
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Revision: 2004 November 2004 FX35/FX45
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.
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 (J-42220) 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 opening indi-
cates 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 (J-43872) to prevent future misdiag-
nosis.
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 (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 J-41459 (refer to the manufacture′s operat-
ing 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.
AUDIO
AV-41
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Revision: 2004 November 2004 FX35/FX45
3. CHECK SPIRAL CABLE
1. Disconnect spiral cable connector (Audio steering wheel switch harness side).
2. Check continuity between spiral cable connector terminal 24,
31, 32 and terminal 20, 17, 16.
OK or NG
OK >> GO TO 4
NG >> Replace spiral cable.
4. CHECK AUDIO STEERING WHEEL SWITCH
Check resistance audio steering wheel switch connector M203 ter-
minals.
OK or NG
OK >> Replace A/C and AV switch.
NG >> Replace audio steering wheel switch.
A/C and AV Switch InspectionAKS00BMU
1. A/C AND AV SWITCH SELF-DIAGNOSIS FUNCTION
1. Start A/C and AV switch self-diagnosis function. Refer to AV- 3 5 , "
A/C and AV Switch Self-Diagnosis Func-
tion" .
2. Operate A/C and AV switch.
Does the A/C and AV switch is operated normally?
YES >> INSPECTION END (System is OK)
NO >> GO TO 2.
2. CHECK A/C AND AV SWITCH POWER SUPPLY AND GROUND
Check A/C and AV switch power supply and gruoud circuit. Refer to AV- 8 0 , "
Power Supply and Ground Circuit
Check for A/C and AV Switch" (Without Navigation System), AV- 1 4 9 , "Power Supply and Ground Circuit
Check for A/C and AV Switch" (With Navigation System).
OK or NG
OK >> Replace A/C and AV switch.
NG >> Repair malfunctioning parts.24 – 20 : Continuity should exist.
31 – 17 : Continuity should exist.
32 – 16 : Continuity should exist.
SKIB0521E
Terminal Switch name ConditionResistance
(Ω)
16
17Power Depress power switch. Approx. 0
Seek down Depress seek down switch. Approx. 165
Volume (down) Depress volume down switch. Approx. 652
20Mode Depress mode switch. Approx. 0
Seek up Depress seek up switch. Approx. 165
Volume (up) Depress volume up switch. Approx. 652
SKIA9400E