5 CHECK COOLING FAN HIGH SPEED OPERATION
Without CONSULT-II
1. Turn ignition switch “OFF”.
2. Reconnect cooling fan relay-3.
3. Turn air conditioner switch and blower fan switch “OFF”.
4. Disconnect engine coolant temperature sensor harness connector.
5. Connect 150Ωresistor to engine coolant temperature sensor harness connector.
6. Restart engine and make sure that cooling fans-1 and -2 operate at high speed.
MEC475B
OK or NG
OK GO TO 6.
NG Check cooling fan high speed control circuit. (Go to PROCEDURE B, EC-141.)
6 CHECK COOLING SYSTEM FOR LEAK
Apply pressure to the cooling system with a tester, and check if the pressure drops.
Testing pressure: 157 kPa (1.57 bar, 1.6 kg/cm2,23psi)
CAUTION:
Higher than the specified pressure may cause radiator damage.
SLC754A
Pressure should not drop.
OK or NG
OK GO TO 8.
NG GO TO 7.
7 DETECT MALFUNCTIONING PART
Check the following for leak.
Hose
Radiator
Water pump (Refer to LC-38, “Water Pump”.)
Repair or replace.
DTC P1217 OVER HEATYD
Diagnostic Procedure (Cont’d)
EC-136
ATC-2
Discharge Air Flow ................................................. 27
System Description ................................................. 28
SWITCHES AND THEIR CONTROL FUNCTION ... 28
TROUBLE DIAGNOSIS ............................................ 29
How to Perform Trouble Diagnoses for Quick and
Accurate Repair ...................................................... 29
WORK FLOW ...................................................... 29
SYMPTOM TABLE .............................................. 29
Component Parts and Harness Connector Location ... 30
ENGINE COMPARTMENT .................................. 30
PASSENGER COMPARTMENT .......................... 31
Circuit Diagram ....................................................... 32
Wiring Diagram ....................................................... 33
Auto Amp. Terminals and Reference Value ............ 40
PIN CONNECTOR TERMINAL LAYOUT ............ 40
AUTO AMP. INSPECTION TABLE ...................... 40
Self-diagnosis Function .......................................... 42
DESCRIPTION .................................................... 42
FUNCTION CONFIRMATION PROCEDURE ...... 43
AUXILIARY MECHANISM: TEMPERATURE
SETTING TRIMMER ........................................... 49
Operational Check .................................................. 51
CHECKING MEMORY FUNCTION ..................... 51
CHECKING BLOWER ......................................... 51
CHECKING DISCHARGE AIR ............................ 52
CHECKING RECIRCULATION ............................ 53
CHECKING FRESH SWITCH ............................. 53
CHECKING TEMPERATURE DECREASE ......... 53
CHECKING TEMPERATURE INCREASE .......... 53
CHECKING AUTO MODE ................................... 54
Power Supply and Ground Circuit for Auto Amp. ... 55
INSPECTION FLOW ........................................... 55
COMPONENT DESCRIPTION ............................ 55
DIAGNOSTIC PROCEDURE FOR A/C SYSTEM ... 56
LAN System Circuit ............................................. ... 57
DIAGNOSTIC PROCEDURE FOR LAN SYS-
TEM CIRCUIT ..................................................... 57
Mode Door Motor Circuit ........................................ 59
INSPECTION FLOW ........................................... 60
SYSTEM DESCRIPTION .................................... 61
COMPONENT DESCRIPTION ............................ 62
DIAGNOSTIC PROCEDURE FOR MODE
DOOR .................................................................. 62
Air Mix Door Motor Circuit ...................................... 63
INSPECTION FLOW ........................................... 63
SYSTEM DESCRIPTION .................................... 64
COMPONENT DESCRIPTION ............................ 65
DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR ................................................... 65
Intake Door Motor Circuit ........................................ 66
INSPECTION FLOW ........................................... 66
SYSTEM DESCRIPTION .................................
... 67
COMPONENT DESCRIPTION ............................ 67
DIAGNOSTIC PROCEDURE FOR INTAKE
DOOR MOTOR ................................................... 68
Blower Motor Circuit ............................................... 69
INSPECTION FLOW ........................................... 69
SYSTEM DESCRIPTION .................................... 70
COMPONENT DESCRIPTION ............................ 71DIAGNOSTIC PROCEDURE FOR BLOWER
MOTOR ................................................................ 71
COMPONENT INSPECTION ............................... 74
Magnet Clutch Circuit .............................................. 75
INSPECTION FLOW ............................................ 75
SYSTEM DESCRIPTION ..................................... 76
DIAGNOSTIC PROCEDURE FOR MAGNET
CLUTCH (WITH CAN SYSTEM) ......................... 76
DIAGNOSTIC PROCEDURE FOR MAGNET
CLUTCH (YD ENGINE WITHOUT COMMON
RAIL) .................................................................... 81
COMPONENT INSPECTION ............................... 85
Insufficient Cooling .................................................. 86
INSPECTION FLOW ............................................ 86
PERFORMANCE TEST DIAGNOSES ................ 88
PERFORMANCE CHART .................................... 90
TROUBLE DIAGNOSES FOR UNUSUAL PRES-
SURE ................................................................... 92
Insufficient Heating ................................................. 95
INSPECTION FLOW ............................................ 95
Noise ....................................................................... 97
INSPECTION FLOW ............................................ 97
Self-diagnosis ......................................................... 98
INSPECTION FLOW ............................................ 98
Memory Function .................................................... 99
INSPECTION FLOW ............................................ 99
Ambient Sensor Circuit .........................................100
COMPONENT DESCRIPTION ..........................100
AMBIENT TEMPERATURE INPUT PROCESS .100
DIAGNOSTIC PROCEDURE FOR AMBIENT
SENSOR ............................................................100
COMPONENT INSPECTION .............................102
In-vehicle Sensor Circuit .......................................102
COMPONENT DESCRIPTION ..........................102
DIAGNOSTIC PROCEDURE FOR IN-VEHICLE
SENSOR ............................................................103
COMPONENT INSPECTION .............................104
Sunload Sensor Circuit .........................................105
COMPONENT DESCRIPTION ..........................105
SUNLOAD INPUT PROCESS ...........................105
DIAGNOSTIC PROCEDURE FOR SUNLOAD
SENSOR ............................................................105
COMPONENT INSPECTION .............................107
Intake Sensor Circuit .............................................108
COMPONENT DESCRIPTION ..........................108
DIAGNOSTIC PROCEDURE FOR INTAKE SEN-
SOR ...................................................................108
Multiplex Communication Circuit ...........................109
DIAGNOSTIC PROCEDURE FOR MULTIPLEX
COMMUNICATION CIRCUIT ............................109
CONTROLLER ........................................................113
Removal and Installation .......................................113
AUTO AMP ..............................................................114
REMOVAL AND INSTALLATION ..........................114
AMBIENT SENSOR ................................................115
Removal and Installation .......................................115
IN-VEHICLE SENSOR ............................................116
Removal and Installation .......................................116
ATC-3
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AT C SUNLOAD SENSOR ...............................................117
Removal and Installation ....................................... 117
INTAKE SENSOR CIRCUIT ....................................118
Removal and Installation ....................................... 118
BLOWER UNIT ........................................................119
Removal and Installation ....................................... 119
REMOVAL .......................................................... 119
INSTALLATION .................................................. 119
Disassembly and Assembly .................................. 119
BLOWER MOTOR .................................................. 120
Removal and Installation ...................................... 120
INTAKE DOOR MOTOR ......................................... 121
Removal and Installation ...................................... 121
HEATER & COOLING UNIT ASSEMBLY .............. 122
Removal and Installation ...................................... 122
REMOVAL ......................................................... 122
INSTALLATION ................................................. 123
Disassembly and Assembly ................................. 123
MODE DOOR MOTOR ........................................... 125
Removal and Installation ...................................... 125
AIR MIX DOOR MOTOR ......................................... 126
Removal and Installation ...................................... 126
FAN CONTROL AMPLIFIER .................................. 127
Removal and Installation ...................................... 127
VENTILATION AIR FILTER .................................... 128
Removal and Installation ...................................... 128
FUNCTION ........................................................ 128
REPLACEMENT TIMING .................................. 128
REPLACEMENT AND PROCEDURES ............ 128
HEATER CORE ...................................................... 129
Removal and Installation ...................................... 129
DUCTS AND GRILLES .......................................... 130
Removal and Installation ...................................... 130
VENTILATOR DUCT, DEFROSTER NOZZLE
AND DEFROSTER DUCTS .............................. 130
CENTER VENTILATOR GRILLE ...................... 130
SIDE VENTILATOR GRILLE ............................. 130
FOOT DUCT ..................................................... 130
FLOOR DUCT ................................................... 131
REFRIGERANT LINES ........................................... 132
HFC-134a (R-134a) Service Procedure ............... 132
SETTING OF SERVICE TOOLS AND EQUIP-
MENT ................................................................ 132Components .........................................................134
Compressor ..........................................................136
REMOVAL .........................................................136
INSTALLATION .................................................137
Compressor Clutch .............................................. .138
REMOVAL .........................................................138
INSTALLATION .................................................139
Low-pressure Flexible Hose .................................141
REMOVAL .........................................................141
INSTALLATION .................................................141
High-pressure Flexible Hose ................................141
REMOVAL .........................................................141
INSTALLATION .................................................142
High-pressure Pipe ...............................................142
REMOVAL .........................................................142
INSTALLATION .................................................142
Refrigerant Pressure Sensor ................................142
REMOVAL AND INSTALLATION ......................142
Dual-pressure Switch ...........................................143
REMOVAL AND INSTALLATION ......................143
Condenser Assembly ...........................................143
REMOVAL .........................................................143
INSTALLATION .................................................143
Evaporator ............................................................144
REMOVAL .........................................................144
INSTALLATION .................................................144
Expansion Valve ...................................................144
REMOVAL .........................................................144
INSTALLATION .................................................144
Checking for Refrigerant Leaks ............................145
Checking System for Leaks Using the Fluorescent
Leak Detector .......................................................145
Dye Injection .........................................................146
Electronic Refrigerant Leak Detector ....................146
PRECAUTIONS FOR HANDLING LEAK
DETECTOR .......................................................146
CHECKING PROCEDURE ...............................147
SERVICE DATA AND SPECIFICATIONS (SDS) ....149
Compressor ..........................................................149
Lubricant ...............................................................149
Refrigerant ............................................................149
Engine Idling Speed .............................................149
Belt Tension ..........................................................149
ATC-20
LUBRICANT
LUBRICANT
PFP:KLG00
Maintenance of Lubricant Quantity in CompressorEJS001Z4
The lubricant in the compressor circulates through the system with the refrigerant. Add lubricant to compres-
sor when replacing any component or after a large gas leakage occurred. It is important to maintain the speci-
fied amount.
If lubricant quantity is not maintained properly, the following malfunctions may result:
●Lack of lubricant: May lead to a seized compressor
●Excessive lubricant: Inadequate cooling (thermal exchange interference)
LUBRICANT
LUBRICANT RETURN OPERATION
Adjust the lubricant quantity according to the test group shown below.
1. CHECK LUBRICANT RETURN OPERATION
Can lubricant return operation be performed?
●A/C system works properly.
●There is no evidence of a large amount of lubricant leakage.
Ye s o r N o
Yes >> GO TO 2.
No >> GO TO 3.
2. PERFORM LUBRICANT RETURN OPERATION, PROCEEDING AS FOLLOWS:
1. Start engine, and set the following conditions:
–Test condition
Engine speed: Idling to 1,200 rpm
A/C or AUTO switch: ON
Blower speed: Max. position
Temp. control: Optional [Set so that intake air temperature is 25 to 30°C (77 to 86°F).]
Intake position: Recirculation (REC)
2. Perform lubricant return operation for about 10 minutes.
3. Stop engine.
CAUTION:
If excessive lubricant leakage is noted, do not perform the lubricant return operation.
>> GO TO 3.
3. CHECK COMPRESSOR
Should the compressor be replaced?
Ye s o r N o
Ye s > > G o t o AT C - 2 1 , "LUBRICANT ADJUSTING PROCEDURE FOR COMPRESSOR REPLACE-
MENT" .
No >> GO TO 4.Name Nissan A/C System Oil Type S
Part number KLH00-PAGS0
ATC-24
AIR CONDITIONER CONTROL
FAN SPEED CONTROL
Blower speed is automatically controlled based on temperature setting, ambient temperature, in-vehicle tem-
perature, intake temperature, amount of sunload and air mix door position.
With FAN switch set to AUTO, the blower motor starts to gradually increase air flow volume.
When engine coolant temperature is low, the blower motor operation is delayed to prevent cool air from flow-
ing.
INTAKE DOOR CONTROL
The intake doors are automatically controlled by: The temperature setting, ambient temperature, in-vehicle
temperature, intake temperature, amount of sunload and ON-OFF operation of the compressor.
OUTLET DOOR CONTROL
The outlet door is automatically controlled by: The temperature setting, ambient temperature, in-vehicle tem-
perature, intake temperature and amount of sunload.
MAGNET CLUTCH CONTROL
The ECM controls compressor operation using input signals from the refrigerant pressure sensor (with QG
engine), throttle position sensor and auto amplifier.
SELF-DIAGNOSTIC SYSTEM
The self-diagnostic system is built into the auto amplifier (LCU) to quickly locate the cause of problems.
Overview of Control systemEJS001Z7
The control system consists of input sensors, switches, the automatic amplifier (microcomputer) and outputs.
The relationship of these components is shown in the diagram below:
RJIA0687E
TROUBLE DIAGNOSIS
ATC-41
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10 L/RMultiplex communication
(Rx) signal
AV → A/C amp.IGN
ON-
11 B/Y Sensor ground IGN
ON-Approx. 0
12 OR Sunload sensorIGN
ON--
17 PU/WWater temperature sen-
sor signalIGN
ONEngine coolant temperature: Approx.
60°C
18 BR/WCompressor feed back
signal (With gasoline
engine)IGN
ONA/C ON-Approx. 0
When refrigerant pres-
sure sensor connector is
disconnected.Approx. 5
20 LMultiplex communication
(CLK) signalIGN
ON-
21 G/YPower supply for mode
door, air mix door and
intake door motorIGN
ON-Approx. 12
22 L/R Compressor ON signalIGN
ONCompressor: ON Approx. 0
Compressor: OFF Approx. 5
24 B GroundIGN
ON-Approx. 0
26 R/B Power supply for BATTIGN
OFF-Approx. 12
27 Y/G Power supply for IGNIGN
ON-Approx. 12
29 LG/B Fan ON signalIGN
ONBlower fan: ON Approx. 0
Blower fan: OFF Approx. 5
33 L/W Power supply for ACCIGN
ON-Approx. 12
34 L/BBlower fan motor feed
back signalIGN
ONFan speed: Manual 1st Approx. 8
35 L/YFan control amp. control
signalIGN
ONFan speed:Manual 1st - 4th speed Approx. 2.5 - 3.5
Manual 5th speed Approx. 9.0 TERMI-
NAL NO.WIRE
COLORITEM CONDITIONVo lta g e
(V)
RJIA0213E
SKIA0056J
HAK0363D
ATC-42
TROUBLE DIAGNOSIS
Self-diagnosis Function
EJS001ZH
DESCRIPTION
The self-diagnostic system diagnoses sensors, door motors, blower motor, etc. by system line. Refer to appli-
cable sections (items) for details. Shifting from usual control to the self-diagnostic system is accomplished by
starting the engine (turning the ignition switch from OFF to ON) and pressing OFF switch for at least 5 sec-
onds. The “OFF” switch must be pressed within 10 seconds after starting the engine (ignition switch is turned
ON). This system will be canceled by either pressing A/C switch or turning the ignition switch OFF. Shifting
from one step to another is accomplished by means of turning temperature dial, as required.
Additionally shifting from STEP 6 to AUXILIARY MECHANISM is accomplished by means of pushing (fan)
UP switch.
RJIA1681E
TROUBLE DIAGNOSIS
ATC-51
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Operational CheckEJS001ZI
The purpose of the operational check is to confirm that the system operates properly.
CHECKING MEMORY FUNCTION
1. Set the temperature 90°F or 32°C.
2. Press OFF switch.
3. Turn the ignition switch OFF.
4. Turn the ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous tempera-
ture.
7. Press OFF switch.
If NG, go to ATC-99, "
Memory Function" .
If OK, continue with next check.
CHECKING BLOWER
1. Press fan switch (up side) one time. Blower should operate on
low speed.The fan symbol should have one blade lit .
2. Press fan switch (up side) one more time, and continue check-
ing blower speed and fan symbol until all speeds are checked.
3. Leave blower on MAX speed.
If NG, go to ATC-69, "
Blower Motor Circuit" .
If OK, continue with next check.Conditions :Engine running and at usual operating temperature
RJIA1683E
RJIA1684E