sensor NISSAN PATROL 1998 Y61 / 5.G Heather And Air Conditioner Workshop Manual

HEATER &
AIR CONDITIONER
SECTION
HA
CONTENTS
MANUAL AND AUTO
PRECAUTIONS AND PREPARATION............................1
Supplemental Restraint System (SRS) ``AIR
BAG'' and ``SEAT BELT PRE-TENSIONER'' ...............1
Precautions for Working with HFC-134a (R-134a) .....1
General Refrigerant Precautions .................................2
Precautions for Refrigerant Connection ......................2
Precautions for Servicing Compressor ........................6
Special Service Tools ..................................................6
HFC-134a (R-134a) Service Tools and
Equipment ....................................................................7
Precautions for Service Equipment .............................9
DESCRIPTION............................................................... 11
Refrigeration Cycle .................................................... 11
Component Layout ....................................................12
Discharge Air Flow.....................................................13
REAR HEATER
TROUBLE DIAGNOSES...............................................14
Wiring Diagram Ð R/HEAT Ð/LHD Models .............14
Wiring Diagram Ð R/HEAT Ð/RHD Models .............15
MANUAL
DESCRIPTION...............................................................16
System Description ....................................................16
Control Operation ......................................................16
TROUBLE DIAGNOSES...............................................17
Component Location..................................................17
Wiring Diagram Ð A/C, M Ð ....................................19
How to Perform Trouble Diagnoses for Quick
and Accurate Repair ..................................................21
Operational Check .....................................................22
Intake Door Motor ......................................................24
Blower Motor..............................................................28
Insufficient Cooling ....................................................32
Trouble Diagnoses for Abnormal Pressure ...............36
Insufficient Heating ....................................................39Air Outlet ....................................................................41
Magnet Clutch............................................................43
Noise ..........................................................................48
AUTO
DESCRIPTION...............................................................49
Introduction ................................................................49
Features .....................................................................49
Overview of Control System ......................................52
Control Operation ......................................................53
TROUBLE DIAGNOSES...............................................55
Component Location..................................................55
Circuit Diagram ..........................................................57
Wiring Diagram Ð A/C, A Ð .....................................58
Auto Amp. Terminals and Reference Value...............61
Self-diagnosis ............................................................63
How to Perform Trouble Diagnoses for Quick
and Accurate Repair ..................................................69
Operational Check .....................................................70
A/C System ................................................................73
Mode Door Motor.......................................................75
Air Mix Door Motor ....................................................79
Intake Door Motor ......................................................82
Blower Motor..............................................................86
Magnet Clutch............................................................92
Insufficient Cooling ....................................................98
Insufficient Heating ....................................................99
Noise ........................................................................100
Self-diagnosis ..........................................................101
Memory Function .....................................................102
Ambient Sensor .......................................................103
In-vehicle Sensor .....................................................105
Sunload Sensor .......................................................107
Intake Sensor........................................................... 110
HA

Supplemental Restraint System (SRS) ``AIR
BAG'' and ``SEAT BELT PRE-TENSIONER''
The Supplemental Restraint System such as ``AIR BAG'' and ``SEAT BELT PRE-TENSIONER'' used along with
a seat belt, helps to reduce the risk or severity of injury to the driver and front passenger in a frontal collision.
The SRS system composition which is available to NISSAN MODEL Y61 is as follows (The composition var-
ies according to the destination.):
Driver air bag module (located in the center of the steering wheel), front passenger air bag module (located
on the instrument panel on passenger side), seat belt pre-tensioner, a diagnosis sensor unit, warning lamp,
wiring harness and spiral cable.
Information necessary to service the system safely is included in theRS sectionof this Service Manual.
WARNING:
+To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag in¯ation, all maintenance must be performed
by an authorized NISSAN dealer.
+Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the RS section.
+Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. Spiral cable and wiring harnesses covered with yellow insulation either just before
the harness connectors or for the complete harness are related to the SRS.
Precautions for Working with HFC-134a
(R-134a)
WARNING:
+CFC-12 (R-12) refrigerant and HFC-134a (R-134a) refrigerant are not compatible. These refriger-
ants must never be mixed, even in the smallest amounts. If the refrigerants are mixed, compres-
sor failure is likely to occur.
+Use only speci®ed lubricant for the HFC-134a (R-134a) A/C system and HFC-134a (R-134a) com-
ponents. If lubricant other than that speci®ed is used, compressor failure is likely to occur.
+The speci®ed HFC-134a (R-134a) lubricant rapidly absorbs moisture from the atmosphere. The
following handling precautions must be observed:
a: When removing refrigerant components from a vehicle, immediately cap (seal) the component
to minimize the entry of moisture from the atmosphere.
b: When installing refrigerant components to a vehicle, do not remove the caps (unseal) until
just before connecting the components. Connect all refrigerant loop components as quickly
as possible to minimize the entry of moisture into system.
c: Only use the speci®ed lubricant from a sealed container. Immediately reseal containers of
lubricant. Without proper sealing, lubricant will become moisture saturated and should not
be used.
d: Avoid breathing A/C refrigerant and lubricant vapor or mist. Exposure may irritate eyes, nose
and throat. Use only approved recovery/recycling equipment to discharge HFC-134a (R-134a)
refrigerant. If accidental system discharge occurs, ventilate work area before resuming ser-
vice. Additional health and safety information may be obtained from refrigerant and lubricant
manufacturers.
e: Do not allow lubricant (Nissan A/C System Oil Type S) to come in contact with styrofoam
parts. Damage may result.
PRECAUTIONS AND PREPARATIONMANUAL AND AUTO
HA-1

Introduction
AIR CONDITIONER LAN SYSTEM OVERVIEW CONTROL SYSTEM
The LAN system consists of auto amp., air mix door motor and mode door motor.
A con®guration of these components is shown in the diagram below.
Features
SYSTEM CONSTRUCTION (LAN)
A small network is constructed between the auto ampli®er, air mix door motor and mode door motor. The auto
ampli®er and motors are connected by data transmission lines and motor power supply lines. The LAN net-
work is built through the ground circuits of the two motors.
Addresses, motor opening angle signals, motor stop signals and error checking messages are all transmitted
through the data transmission lines connecting the auto ampli®er and two motors.
The following functions are contained in LCUs built into the air mix door motor and the mode door motor.
+Address
+Motor opening angle signals
+Data transmission
+Motor stop and drive decision
+Opening angle sensor (PBR function)
+Comparison
+Decision (Auto ampli®er indicated value and motor opening angle comparison)
RHA439G
RHA440GA
DESCRIPTIONAUTO
HA-49

Operation
The auto ampli®er receives data from each of the sensors. The ampli®er sends air mix door and mode door
opening angle data to the air mix door motor LCU and mode door motor LCU.
The air mix door motor and mode door motor read their respective signals according to the address signal.
Opening angle indication signals received from the auto ampli®er and each of the motor position sensors are
compared by the LCUs in each motor with the existing decision and opening angles. Subsequently, HOT/
COLD or DEFROST/VENT operation is selected. The new selection data is returned to the auto ampli®er.
Transmission data and transmission order
Ampli®er data is transmitted consecutively to each of the door motors following the form shown in ®gure below.
Start: Initial compulsory signal sent to each of the door motors.
Address: Data sent from the auto ampli®er is selected according to data-based decisions made by the air mix
door motor and mode door motor.
If the addresses are identical, the opening angle data and error check signals are received by the door motor
LCUs. The LCUs then make the appropriate error decision. If the opening angle data is normal, door control
begins.
If an error exists, the received data is rejected and corrected data received. Finally, door control is based upon
the corrected opening angle data.
Opening angle: Data that shows the indicated door opening angle of each door motor.
Error check: Procedure by which sent and received data is checked for errors. Error data is then compiled.
The error check prevents corrupted data from being used by the air mix door motor and mode door motor.
Error data can be related to the following problems.
+Abnormal electrical frequency
+Poor electrical connections
+Signal leakage from transmission lines
+Signal level ¯uctuation
Stop signal: At the end of each transmission, a stop operation, in-operation, or internal problem message is
delivered to the auto ampli®er. This completes one data transmission and control cycle.
RHA441GA
DESCRIPTIONAUTO
Features (Cont'd)
HA-50

Air mix door control (Automatic temperature control)
The air mix door is automatically controlled so that in-vehicle temperature is maintained at a predetermined
value by: The temperature setting, ambient temperature, in-vehicle temperature and amount of sunload.
Fan speed control
Blower speed is automatically controlled based on temperature setting, ambient temperature, in-vehicle
temperature, intake temperature, amount of sunload and air mix door position.
With FAN switch set to ``AUTO'', the blower motor starts to gradually increase air ¯ow volume.
When engine coolant temperature is low, the blower motor operation is delayed to prevent cool air from ¯ow-
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
temperature, intake temperature and amount of sunload.
Magnet clutch control
The ECM (ECCS control module) controls compressor operation using input signals from the throttle position
sensor and auto ampli®er.
Self-diagnostic system
The self-diagnostic system is built into the auto ampli®er (LCU) to quickly locate the cause of problems.
RHA442G
DESCRIPTIONAUTO
Features (Cont'd)
HA-51

Overview of Control System
The control system consists of input sensors, switches, the automatic ampli®er (microcomputer) and outputs.
The relationship of these components is shown in the diagram below:
RHA732G
DESCRIPTIONAUTO
HA-52

AUTO AMP. INSPECTION TABLE
TERMINAL
No.ITEM CONDITIONVoltage
V
1 Power supply for IGN
Ð Approximately 12
2 Power supply for BAT
Ð Approximately 12
3 Ground Ð Ð
4 Compressor ON signal
CompressorON Approximately 0
OFF Approximately 12
5Power supply for mode and air mix
door motor
Ð Approximately 12
8 In-vehicle sensor Ð Ð
9 Ambient sensor Ð Ð
10 Sunload sensor Ð Ð
11 Ground Ð Ð
12 Power supply for illumination
Illumination switch ON Approximately 12
13 Intake door position switchRECIRCULATION Approximately 0
FRESH or 20% FRESH Approximately 12
14 Intake door position switchFRESH Approximately 0
RECIRCULATION or 20% FRESH Approximately 12
15 LAN signal Ð Approximately 5.5
17 Fan control amp. control signal Fan speedLow, middle low or middle high Approximately 2.5 - 3.0
High Approximately9-10
18 Blower motor feed back Ð Approximately 12
20 Power supply for blower motor
Ð Approximately 12
21 Thermal transmitter Ð Ð
23 Intake door position switch
20% FRESH Approximately 0
RECIRCULATION or FRESH Approximately 12
24 Sensor ground Ð Ð
25 Intake sensor Ð Ð
28 Rear cooler relay
Rear cooler ON Approximately 0
Rear cooler OFF Approximately 12
35 Rear cooler switchRear cooler switch ON Approximately 0
Rear cooler switch OFF Approximately 12
TROUBLE DIAGNOSESAUTO
Auto Amp. Terminals and Reference Value
(Cont'd)
HA-62

Self-diagnosis
INTRODUCTION AND GENERAL DESCRIPTION
The self-diagnostic system diagnoses sensors, door motors,
blower motor, etc. by system line. Refer to applicable sections
(items) for details. Shifting from normal control to the self-diagnos-
tic system is accomplished by starting the engine (turning the igni-
tion switch from ``OFF'' to ``ON'') and pressing ``
'' switch for at
least 5 seconds. The ``
'' switch must be pressed within 5 sec-
onds after starting the engine (ignition switch is turned ``ON''). This
system will be canceled by either pressing
(AUTO) switch or
turning the ignition switch ``OFF''. Shifting from one step to another
is accomplished by means of turning temperature dial clockwise or
counterclockwise, as required.
Additionally shifting from STEP 4 to AUXILIARY MECHANISM is
accomplished by means of pushing
(fan) switch.
(Ignition switch OFF®ON)
Within 5 seconds after starting engine (ignition
switch is turned ``ON''), press
switch for
at least 5 seconds.
STEP 1 Ð LEDs and LCD are checked.
m
Left turnRight turn
STEP 2 Ð Input signals from each sensor are
checked.
m
Left turnRight turn
STEP 3 Ð Mode and intake door motor posi-
tion switch is checked.Ignition switch: OFFc
or(AUTO) switch: ONSelf-diagnostic function is canceled.m
Left turnRight turn
Note
STEP 4 Ð Actuators are checked.
m
AUXILIARY MECHANISM Ð Temperature set-
ting trimmerNote:
For STEP 4, engine must be running for
compressor to operate.
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
HA-63

jA
STEP 2 - SENSOR CIRCUITS ARE
CHECKED FOR OPEN OR SHORT
CIRCUIT.
Does code No.
appear on the dis-
play?
Ye sNo
.
Turn temperature
dial clockwise.Refer to the following chart for malfunctioning code
No.
(If two or more sensors malfunction, corresponding
code Nos. blink respectively two times.)
*1: Conduct self-diagnosis STEP 2 under sunshine.
When conducting indoors, aim a light (more than
60W) at sunload sensor, otherwise Code No.
will indicate despite that sunload sensor is func-
tioning properly. j
B
(Go to next page.)
Code No.Malfunctioning sensor
(including circuits)Reference
page
Ambient sensor HA-103A/C LED
In-vehicle sensor HA-105A/C LED
Sunload sensor*1 HA-107A/C LED
Air mix door motor
(LCU) PBRHA-79
A/C LED
RHA970DA
RHA528G
RHA501A
.
.
.
TROUBLE DIAGNOSESAUTO
Self-diagnosis (Cont'd)
HA-65

A/C System
TROUBLE DIAGNOSIS PROCEDURE FOR A/C SYSTEM
SYMPTOM:
+A/C system does not come on.
Inspection ¯ow
*1: HA-74 *2: HA-70
COMPONENT DESCRIPTION
Automatic ampli®er (Auto amp.)
The auto ampli®er has a built-in microcomputer which processes
information sent from various sensors needed for air conditioner
operation. The air mix door motor, mode door motor, intake door
motor, blower motor and compressor are then controlled.
The auto ampli®er is unitized with control mechanisms. Signals
from various switches and Potentio Temperature Control (PTC) are
directly entered into auto ampli®er.
Self-diagnostic functions are also built into auto ampli®er to provide
quick check of malfunctions in the auto air conditioner system.
Potentio temperature control (PTC)
The PTC is built into the A/C auto amp. It can be set at an interval
of 1ÉC in the 18ÉC to 32ÉC temperature range by turning the tem-
perature dial. The set temperature is digitally displayed.
SHA019F
RHA629G
RHA746G
TROUBLE DIAGNOSESAUTO
HA-73