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

YHA160
TROUBLE DIAGNOSESAUTO
Wiring Diagram Ð A/C, A Ð (Cont'd)
HA-59

YHA161
TROUBLE DIAGNOSESAUTO
Wiring Diagram Ð A/C, A Ð (Cont'd)
HA-60

Auto Amp. Terminals and Reference Value
INSPECTION OF AUTO AMP.
+Measure voltage between each terminal and body ground by
following ``AUTO AMP. INSPECTION TABLE''.
+Pin connector terminal layout
RHA629G
RHA630G
TROUBLE DIAGNOSESAUTO
HA-61

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

STEP-BY-STEP PROCEDURE
Turn ignition switch ON.
Set in self-diagnostic mode. Within 5 sec-
onds after starting engine (ignition switch is
turned ``ON''.), press
switch for at
least 5 seconds.
STEP 1 - LEDs AND LCD ARE CHECKED.
Do all LEDs and LCD illuminate?
Ye s
cNo
Malfunctioning
switch, LED or LCD.
Replace A/C auto amp.
Turn temperature dial clockwise.
Advance to self-diagnosis STEP 2?
Ye s
cNo
Malfunctioning temperature
dial.
Replace A/C auto amp.
Turn temperature dial counterclockwise.
Return to self-diagnosis STEP 1?
Ye s
cNo
Malfunctioning temperature
dial.
Replace A/C auto amp.
Turn temperature dial clockwise.
jA
(Go to next page.)
RHA526G
RHA527G
.
.
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Self-diagnosis (Cont'd)
HA-64

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

jB
STEP 3 - MODE DOOR POSITIONS
ARE CHECKED.
Does code No.
appear on the dis-
play?
Ye sNo
.
Turn temperature
dial clockwise.Mode door motor position switch is malfunctioning.
(If two or more mode doors are out of order, corre-
sponding code numbers blink respectively two
times.)
*1: If mode door motor harness connector is
disconnected, the following display pattern will
appear.
®
®®®®þ
jC
(Go to next page.)
Code
No.*1Mode door positionReference
page
VENT
HA-75
B/L
FOOT
F/D
DEF
RHA869DC
RHA168DA
RHA498A
.
.
.
TROUBLE DIAGNOSESAUTO
Self-diagnosis (Cont'd)
HA-66

jC
STEP 4 - OPERATION OF EACH ACTUA-
TOR IS CHECKED.
Engine running.
Press DEF switch, code No. of each actua-
tor test is indicated on the display.
Refer to the following chart and con®rm
discharge air ¯ow, air temperature, blower
motor voltage and compressor operation.
Checks must be made visually, by lis-
tening to any noise, or by touching air
outlets with your hand, etc. for
improper operation.
OK
cNG
+Air outlet does not
change.
Go to HA-75.
+Intake door does not
change.
Go to HA-82.
+Discharge air tempera-
ture does not change.
Go to HA-79.
+Magnet clutch does not
engage.
Go to HA-92.
+Blower motor operation is
malfunctioning.
Go to HA-86.
Turn ignition switch OFF or AUTO switch
ON.
END
Code
No.Actuator test pattern
Mode doorIntake
doorAir
mix
doorBlower
motorCom-
pres-
sorFICD
VENTRECFull
Cold4-5V ON ON
B/LRECFull
Cold9-
11 VON ON
B/L20%
FREFull
Hot7-9V ON OFF
FOOTFREFull
Hot7 - 9V OFF OFF
F/D
FREFull
Hot7 - 9V OFF OFF
DEFFREFull
Hot10 -
12VON OFF
RHA495A
RHA654FF
.
.
.
.
TROUBLE DIAGNOSESAUTO
Self-diagnosis (Cont'd)
HA-67

AUXILIARY MECHANISM: Temperature setting trimmer
The trimmer compensates for differences in range of  3ÉC between
temperature setting (displayed digitally) and temperature felt by
driver.
Operating procedures for this trimmer are as follows:
+Begin Self-diagnosis STEP 4 mode.
+Press
(fan) switch to set system in auxiliary mode.
+Turn temperature dial clockwise or counterclockwise as
desired. Temperature will change at a rate of 1ÉC each time a
switch is pressed.
When battery cable is disconnected, trimmer operation is can-
celed. Temperature set becomes that of initial condition, i.e.
0ÉC.
RHA581G
TROUBLE DIAGNOSESAUTO
Self-diagnosis (Cont'd)
HA-68