1999 NISSAN PICK-UP Repair Manual

HHA189
TROUBLE DIAGNOSESAUTO
Wiring Diagram Ð A/C, A Ð (Cont'd)
HA-2029

HHA190
TROUBLE DIAGNOSESAUTO
Wiring Diagram Ð A/C, A Ð (Cont'd)
HA-2030

HHA191
TROUBLE DIAGNOSESAUTO
Wiring Diagram Ð A/C, A Ð (Cont'd)
HA-2031

Auto Amp. Terminals and Reference Value
INSPECTION OF AUTO AMP.
lMeasure voltage between each terminal and body ground by
following ªAUTO AMP. INSPECTION TABLEº.
lPin connector terminal layout
RHA470H
RHA630GA
TROUBLE DIAGNOSESAUTO
HA-2032

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
5 Power supply for air mix door motorSet tem-
perature32ÉC Approximately 12
18ÉC Approximately 0
6 Power supply for air mix door motorSet tem-
perature32ÉC Approximately 0
18ÉC Approximately 12
7 Power supply for PBRApproximately 5
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 *
14 Intake door position switchFresh Approximately 0
Recirculation or 20% Fresh *
15 Power supply for mode motorDEF®VENT Approximately 12
VENT®DEF Approximately 0
16 Power supply for mode motorDEF®VENT Approximately 0
VENT®DEF Approximately 12
17 Fan control amp. control signal Fan speedLow, Middle Low, Middle high Approximately 2.5 - 3.0
High Approximately 9.0
18 Blower motor feed back Fan speed Low Approximately 8
19 Blower fan motor ON signalBlower fan: ON Approximately 0
Blower fan: OFF Approximately 5
20 Power supply for IGN Ð Approximately 12
21 Thermal transmitter Ð Ð
22 Air mix door motor PBR signal
Set tem-
perature32ÉC Approximately 4.5
18ÉC Approximately 0.5
23 Intake door motor position switch20% Fresh Approximately 0
Recirculation or Fresh *
24 Ground Ð Ð
25 Intake sensor Ð Ð
27 FICD ON signal
Compressor
ONAmbient temperature: 20.5ÉC
(69ÉF) or lessApproximately 0
Ambient temperature: 23.5ÉC
(74ÉF) or moreApproximately 12
29 Mode door motor position signalVENT, B/L Approximately 0
FOOT, D/F, DEF Approximately 5
30 Mode door motor position signalB/L, FOOT Approximately 0
VENT, D/F, DEF Approximately 5
31 Mode door motor position signalVENT, FOOT, D/F Approximately 0
B/L, DEF Approximately 5
32 Mode door motor position signalD/F, DEF Approximately 0
VENT, B/L, FOOT Approximatley 5
*: When the motor is working approx. 0V will be indicated. When the motor is stopped, approx. 12V will exist.
TROUBLE DIAGNOSESAUTO
Auto Amp. Terminals and Reference Value
(Cont'd)
HA-2033

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-diag-
nostic system is accomplished by starting the engine (turning the
ignition switch from ªOFFº to ªONº) and pressing ª
º switch for
at least 5 seconds. The ª
º switch must be pressed within 5
seconds after starting the engine (ignition switch is turned ªONº).
This system will be canceled by either pressing
(AUTO)
switch or turning the ignition switch ªOFFº. 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 ªONº), 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-2034

STEP-BY-STEP PROCEDURE
Turn ignition switch ON.
Set in self-diagnostic mode. Within 5 sec-
onds after starting engine (ignition switch
is turned ªONº.), press
switch for at
least 5 seconds.
STEP 1 - LEDs AND LCD ARE
CHECKED.
Do all LEDs and LCD illuminate?
Yes
cNo
Malfunctioning
switch, LED or LCD.
Replace A/C auto amp.
Turn temperature dial clockwise.
Advance to self-diagnosis STEP 2?
Yes
cNo
Malfunctioning temperature
dial.
Replace A/C auto amp.
Turn temperature dial counterclockwise.
Return to self-diagnosis STEP 1?
Yes
cNo
Malfunctioning temperature
dial.
Replace A/C auto amp.
Turn temperature dial clockwise.
VA(Go to next page.)
RHA526G
RHA527G
.
.
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Self-diagnosis (Cont'd)
HA-2035

VA
STEP 2 - SENSOR CIRCUITS ARE
CHECKED FOR OPEN OR SHORT
CIRCUIT.
Does code No.
appear on the dis-
play?
YesNo
.
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.
VB
(Go to next page.)
Code No.Malfunctioning sensor
(including circuits)Reference
page
Ambient sensor HA-2080A/C LED
In-vehicle sensor HA-2082A/C LED
Sunload sensor*1 HA-2084A/C LED
Air mix door motor PBR HA-2055A/C LED
RHA970DA
RHA528G
RHA501A
.
.
.
TROUBLE DIAGNOSESAUTO
Self-diagnosis (Cont'd)
HA-2036