sensor NISSAN PATROL 2006 Service Manual

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

SYSTEM DESCRIPTION
Component parts
Mode door control system components are:
1) Auto amp.
2) Mode door motor (LCU)
3) In-vehicle sensor
4) Ambient sensor
5) Sunload sensor
6) Intake sensor
System 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.
SHA006FA
TROUBLE DIAGNOSESAUTO
Mode Door Motor (Cont'd)
HA-76

SYSTEM DESCRIPTION
Component parts
Air mix door control system components are:
1) Auto amp.
2) Air mix door motor (LCU)
3) In-vehicle sensor
4) Ambient sensor
5) Sunload sensor
6) Intake sensor
System 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.
RHA424GB
TROUBLE DIAGNOSESAUTO
Air Mix Door Motor (Cont'd)
HA-80

SYSTEM DESCRIPTION
Component parts
Intake door control system components are:
1) Auto amp.
2) Intake door motor
3) A/C LAN system (PBR built-in mode motor and air mix door motor)
4) In-vehicle sensor
5) Ambient sensor
6) Sunload sensor
7) Intake sensor
System operation
The intake door control determines intake door position based on the ambient temperature, the intake air
temperature and the in-vehicle temperature. When the A/C, DEFROSTER, or OFF switches are pushed, the
auto ampli®er sets the intake door at the ``Fresh'' position.
RHA640G
TROUBLE DIAGNOSESAUTO
Intake Door Motor (Cont'd)
HA-83

SYSTEM DESCRIPTION
Component parts
Fan speed control system components are:
1) Auto amp.
2) Fan control amp.
3) A/C LAN system (PBR built in mode door motor and air mix door motor)
4) In-vehicle sensor
5) Ambient sensor
6) Sunload sensor
7) Intake sensor
System operation
Automatic mode
In the automatic mode, the blower motor speed is calculated by the automatic ampli®er based on inputs from
the PBR, in-vehicle sensor, sunload sensor, intake sensor and ambient sensor. The blower motor applied
voltage ranges from approximately 5 volts (lowest speed) to 12 volts (highest speed).
The control blower speed (in the range of 5 to 12V), the automatic ampli®er supplies a gate voltage to the fan
control ampli®er. Based on this voltage, the fan control ampli®er controls the voltage supplied to the blower
motor.
Starting fan speed control
Start up from ``COLD SOAK'' condition (Automatic mode)
In a cold start up condition where the engine coolant temperature is below 50ÉC, the blower will not operate
for a short period of time (up to 150 seconds). The exact start delay time varies depending on the ambient
and engine coolant temperature.
In the most extreme case (very low ambient) the blower starting delay will be 150 seconds as described above.
After this delay, the blower will operate at low speed until the engine coolant temperature rises above 55ÉC,
at which time the blower speed will increase to the objective speed.
Start up from normal or ``HOT SOAK'' condition (Automatic mode)
The blower will begin operation momentarily after the AUTO button is pushed. The blower speed will gradu-
ally rise to the objective speed over a time period of 3 seconds or less (actual time depends on the objective
blower speed).
SHA006FB
TROUBLE DIAGNOSESAUTO
Blower Motor (Cont'd)
HA-87

SYSTEM DESCRIPTION
Auto ampli®er controls compressor operation by ambient tempera-
ture and signal from ECM (ECCS control module).
Low temperature protection control
Auto ampli®er will turn the compressor ``ON'' or ``OFF'' as deter-
mined by a signal detected by ambient sensor.
When ambient temperatures are greater than 1ÉC, the compressor
turns ``ON''. The compressor turns ``OFF'' when ambient tempera-
tures are less than þ2ÉC.
RHA094GA
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-93