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

DIAGNOSTIC PROCEDURE
SYMPTOM: Blower motor operation is malfunctioning under
Starting Fan Speed Control.
CHECK POWER SUPPLY FOR FAN
CONTROL AMP.
Disconnect fan control amp. harness con-
nector.
Do approx. 12 volts exist between fan
control amp. harness terminal No.j
1and
body ground?
Ye s
cNo
CHECK POWER SUPPLY
FOR BLOWER MOTOR.
Disconnect blower motor
harness connector.
Do approx. 12 volts exist
between blower motor har-
ness terminal No.j
2and
body ground?
No
.
Ye s
Note
CHECK BODY GROUND CIRCUIT FOR
FAN CONTROL AMP.
Does continuity exist between fan control
amp. harness terminal No.j
3and body
ground?
Ye sCheck
power sup-
ply circuit
and 15A
fuses (No.1and2,
located in
the fuse
block).
Note
Reconnect fan control amp. harness con-
nector.
Check circuit continuity
between blower motor har-
ness terminal No.j
1and
fan control amp. harness
terminal No.j
1.
OK
CHECK FOR AUTO AMP. OUTPUT.
Set up Self-diagnosis STEP 4.
Measure voltage across fan control amp.
harness terminal No.j
2and body ground.
OKCHECK BLOWER
MOTOR.
(Refer to HA-91.)
NG
Replace blower motor.
cNG
jA(Go to next page.)
Replace fan control amp.
Note:If the result is NG or No after checking circuit continuity, repair harness or
connector.
Code No.Terminal No.
VoltageÅ@
þj2Body groundApprox.
2.5-3VApprox.
9 - 10V
RHA087GB
RHA643G
RHA644G
RHA645G
RHA646G
..
.
..
.
.
TROUBLE DIAGNOSESAUTO
Blower Motor (Cont'd)
HA-89

jA
Disconnect auto amp. and fan control amp.
harness connector.
Note
Does continuity exist between auto amp.
harness terminal No.j
17and fan control
amp. harness terminal No.j
2?
Continuity should exist.
If OK, check harness for short.
Ye s
CHECK FAN FEED BACK CIRCUIT.
Do approx. 12 volts exist between auto
amp. harness terminal No.j
20and body
ground?
Ye s
cNo
Check power supply circuit
and 15A fuses (No.
1
and2, located in the fuse
block).
Refer to EL section (``Wiring
Diagram'', ``POWER SUP-
PLY ROUTING'').
Note
Do approx. 12 volts exist between auto
amp. harness terminal No.j
18and body
ground?
Ye s
cNo
Check circuit continuity
between blower motor har-
ness terminal No.j
1and
auto amp. harness terminal
No.j
18.
Continuity should exist.
If OK, check harness for
short.
Replace auto amp.
Note:
If the result is NG or No after checking circuit continuity, repair harness
or connector.
RHA647G
RHA648G
RHA649G
RHA650G
RHA651G
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Blower Motor (Cont'd)
HA-90

COMPONENT INSPECTION
Blower motor
Con®rm smooth rotation of the blower motor.
+Ensure that there are no foreign particles inside the intake unit.
RHA941F
TROUBLE DIAGNOSESAUTO
Blower Motor (Cont'd)
HA-91

Magnet Clutch
TROUBLE DIAGNOSIS PROCEDURE FOR MAGNET CLUTCH
SYMPTOM:
+Magnet clutch does not engage.
Inspection ¯ow
*1: HA-64
*2: HA-65
*3: HA-67
*4: HA-94*5: HA-103
*6: HA-105
*7: HA-107
*8: HA-110*9: HA-79
*10: HA-70
*11: HA-69
*12: HA-35
SHA023F
TROUBLE DIAGNOSESAUTO
HA-92

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

DIAGNOSTIC PROCEDURE
SYMPTOM: Magnet clutch does not engage when A/C switch
and fan switch are ON.
CHECK POWER SUPPLY FOR COM-
PRESSOR.
Disconnect compressor harness connector.
Do approx. 12 volts exist between compres-
sor harness terminal No.j
1and body
ground?
No
cYe s
Check magnet clutch coil.
NG
Replace magnet clutch.
Refer to HA-123.
Disconnect A/C relay.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN A/C RELAY HARNESS TERMI-
NAL NO.j
7AND COMPRESSOR HAR-
NESS TERMINAL NO.j1.
Continuity should exist.
If OK, check harness for short.
OK
CHECK POWER SUPPLY FOR A/C
RELAY.
Disconnect A/C relay.
Do approx. 12 volts exist between A/C
relay harness terminal Nos.j
1,j6and
body ground?
Ye s
cNo
CHECK POWER SUPPLY
CIRCUIT AND 10A (No.
) FUSE AT FUSE
BLOCK.
Refer to EL section (``Wiring
Diagram'', ``POWER SUP-
PLY ROUTING'').
CHECK A/C RELAY AFTER DISCON-
NECTING IT.
Refer to HA-97.
OK OK
ECCS
engine
modelsExcept for
ECCS
engine
models
cNG
Replace A/C relay.
jA(Go to next page.)jB
Note:
If the result is NG or No after checking circuit continuity, repair harness or
connector.
RHA652G
RHA096GA
RHA653G
RHA654G
.
.
.
.
.
..
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-94

jA
Reconnect A/C relay.
CHECK COIL SIDE CIRCUIT OF A/C
RELAY.
Do approx. 12 volts exist between ECM
(ECCS control module) harness terminal
No.j
9and body ground?
Ye s
cNo
Disconnect A/C relay.
Disconnect ECM (ECCS
control module) harness
connector.
Note
CHECK CIRCUIT CONTI-
NUITY BETWEEN A/C
RELAY HARNESS TERMI-
NAL NO.j
2AND ECM
(ECCS CONTROL MOD-
ULE) HARNESS TERMI-
NAL NO.j
9.
Continuity should exist.
If OK, check harness for
short.
CHECK VOLTAGE FOR ECM (ECCS con-
trol module).
Do approx. 12 volts exist between ECM
(ECCS control module) harness terminal
No.j
46and body ground?
Ye s
cNo
CHECK ECM (ECCS con-
trol module). Refer to EC
section.
Disconnect ECM (ECCS control module)
harness connector.
Disconnect dual-pressure switch harness
connector.
Note
CHECK CIRCUIT CONTINUITY
BETWEEN ECM (ECCS CONTROL MOD-
ULE) HARNESS TERMINAL NO.j
46,j21
AND DUAL-PRESSURE SWITCH HAR-
NESS TERMINAL NO.j
2.
Continuity should exist.
If OK, check harness for short.
OK
CHECK DUAL-PRESSURE SWITCH.
Refer to HA-97.
OK
cNG
Replace dual-pressure
switch.
jC
Note:
If the result is NG or No after checking circuit continuity, repair harness
or connector.
RHA655G
RHA656G
RHA657G
RHA658G
.
.
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-95

jB
Note
Check circuit continuity between A/C relay
harness terminal No.j
2and dual-pressure
switch harness terminal No.j
2.
Continuity should exist.
If OK, check harness for short.
Ye s
CHECK DUAL-PRESSURE SWITCH.
Refer to HA-97.
OK
cNG
Replace dual-pressure
switch.
jC
.
CHECK THERMO CONTROL AMP. CIR-
CUIT.
Do approx. 12 volts exist between thermo
control amp. harness terminal No.j
3and
body ground?
Ye s
cNo
jD
CHECK POWER SUPPLY FOR THERMO
AMP.
Do approx. 12 volts exist between thermo
control amp. harness terminal No.j
1and
body ground?
Ye s
cNo
Check power supply circuit
and 10A fuse (No.
,
located in the fuse block).
Note
Check circuit continuity between thermo
control amp. harness terminal No.j
2and
auto amp. harness terminal No.j
4.
Continuity should exist.
If OK, check harness for short.
OK
CHECK THERMO CONTROL AMP.
Refer to HA-47.
OK
cNG
Replace thermo amp.
Replace auto amp.
Note:
If the result is NG or No after checking circuit continuity, repair harness
or connector.
RHA659G
RHA660G
RHA661G
RHA662G
.
.
.
.
.
.
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-96

jD
Note
Check circuit continuity between dual-pres-
sure switch harness terminal No.j
1and
thermo control amp. harness terminal No.
j
3.
Continuity should exist.
If OK, check harness for short.
Note:
If the result is NG or No after checking circuit continuity, repair harness
or connector.
COMPONENT INSPECTION
A/C relay
Check continuity between terminal Nos.j3andj5,j6andj7.
Conditions Continuity
12V direct current supply between terminal Nos.
j
1andj2Ye s
No current supply No
If NG, replace relay.
Dual-pressure switch
ON
kPa (bar, kg/cm2, psi)OFF
kPa (bar, kg/cm2, psi)
Low-pressure
sideIncreasing to
157 - 216 (1.57 - 2.16,
1.6 - 2.2, 23 - 31)Decreasing to
157 - 196 (1.57 - 1.96,
1.6 - 2.0, 23 - 28)
High-pressure
sideDecreasing to
1,863 - 2,256 (18.6 - 22.6,
19 - 23, 270 - 327)Increasing to
2,452 - 2,844 (24.5 - 28.4,
25 - 29, 356 - 412)
RHA663G
SEC202B
RHA628G
.
TROUBLE DIAGNOSESAUTO
Magnet Clutch (Cont'd)
HA-97

Insufficient Cooling
TROUBLE DIAGNOSIS PROCEDURE FOR INSUFFICIENT COOLING
SYMPTOM:
+Insufficient cooling.
Inspection ¯ow
*1: HA-64
*2: HA-65
*3: HA-67
*4: HA-78*5: HA-82
*6: HA-89
*7: HA-94
*8: HA-79*9: HA-33
*10: HA-68
*11: HA-70
SHA053F
TROUBLE DIAGNOSESAUTO
HA-98