1998 NISSAN PATROL Heather And Air Conditioner Workshop Manual

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

How to Perform Trouble Diagnoses for Quick
and Accurate Repair
WORK FLOW
*1: Operational Check (HA-70)
SYMPTOM TABLE
Symptom Reference page
+A/C system does not come on.+Go to Trouble Diagnosis Procedure for A/C system. HA-73
+Air outlet does not change.
+Go to Trouble Diagnosis Procedure for Mode Door Motor.
(LAN).HA-75
+Mode door motor does not operate nor-
mally.
+Discharge air temperature does not
change.
+Go to Trouble Diagnosis Procedure for Air Mix Door Motor
(LAN).HA-79
+Air mix door motor does not operate nor-
mally.
+Intake door does not change.
+Go to Trouble Diagnosis Procedure for Intake Door Motor. HA-82
+Intake door motor does not operate nor-
mally.
+Blower motor operation is malfunctioning.
+Go to Trouble Diagnosis Procedure for Blower Motor. HA-86
+Blower motor operation is malfunctioning
under out of starting fan speed control.
+Magnet clutch does not engage.+Go to Trouble Diagnosis Procedure for Magnet Clutch. HA-92
+Insufficient cooling.+Go to Trouble Diagnosis Procedure for Insufficient Cooling. HA-98
+Insufficient heating.+Go to Trouble Diagnosis Procedure for Insufficient Heating. HA-99
+Noise.+Go to Trouble Diagnosis Procedure for Noise. HA-100
+Self-diagnosis cannot be performed.+Go to Trouble Diagnosis Procedure for Self-diagnosis. HA-101
+Memory function does not operate.+Go to Trouble Diagnosis Procedure for Memory Function. HA-102
SHA900E
TROUBLE DIAGNOSESAUTO
HA-69

Operational Check
The purpose of the operational check is to con®rm that the system
operates properly.
CONDITIONS
+Engine running and at normal operating temperature.
PROCEDURE
1. Check memory function
a. Set the temperature 25ÉC.
b. Press OFF switch.
c. Turn the ignition off.
d. Turn the ignition on.
e. Press the AUTO switch.
f. Con®rm that the set temperature remains at previous tempera-
ture.
g. Press OFF switch.
2. Check blower
a. Press fan switch one time.
Blower should operate on low speed.
The fan symbol should have one blade lit
.
b. Press fan switch one more time, and continue checking blower
speed and fan symbol until all speeds are checked.
c. Leave blower on MAX speed
.
3. Check discharge air
a. Press mode switch four times and DEF button.
RHA517G
RHA518G
RHA519G
RHA520G
TROUBLE DIAGNOSESAUTO
HA-70