2004 NISSAN TERRANO Service Repair Manual

How to Perform Trouble Diagnoses for Quick
and Accurate Repair
WORK FLOW
CHECK INFReference item
LISTEN TO CUSTOMER COMPLAINT AND CON-
FIRM BY PERFORMING OPERATIONAL CHECK.
Can be
confirmedCannot be
confirmed
EDUCATE CUSTOMER ON
CORRECT OPERATION OF
SYSTEM.
LISTEN TO CUSTOMER COMPLAINTS AND
CONFIRM.FSymptom Chart
(See page HA-37.)
INVESTIGATE ITEMS YOU SHOULD CARRY
OUT RELATED TO EACH SYMPTOM.FSymptom Chart
(See page HA-37.)
EELIMINATE GOOD SYSTEM(S)/PART(S).FPreliminary Check
(See pages HA-38.)
CHECK MAIN POWER SUPPLY AND GROUND
CIRCUITS.FMain Power Supply and Ground Circuit
Check
(See page HA-52.)
Diagnostic
Procedure(s)
(See pages HA-53 -
55.)EELIMINATE GOOD PART(S)/HARNESS(ES)/
CONNECTOR(S) ELECTRICALLY.FHarness Layout for A/C System
(See page HA-40.)
Malfunctioning
harness(es)/
connector(s) Malfunctioning
part(s)
INSPECT EACH
COMPONENT.
FElectrical Components Inspection
(See page HA-61.)
REPAIR.
H
REPAIR/REPLACE.
NG FINAL CHECK
OK
CHECK OUT
H
H
H
H
H
H
H
H
HH
H
H
DIAGNOSES Ð Overall System
HA-28
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Operation Check
The purpose of the operational check is to confirm that the system
is as it should be. The systems which will be checked are the
blower, mode (discharge air), intake air, temperature decrease,
temperature increase and A/C switch system.
CONDITIONS:
Engine running and at normal operating temperature.
PROCEDURE:
1. Check blower
1) Turn FAN CONTROL DIAL to 1.Blower should operate at speed 1.
2) Then turn the DIAL to speed 2.
3) Continue checking blower speed until all speeds are checked.
4) Leave blower on speed 4.
2. Check discharge air
1) Turn AIR CONTROL DIAL toposition.
2) Confirm that all discharge air comes out of face vents.
3) Turn AIR CONTROL DIAL to
position.
4) Confirm that discharge air comes out of face vents and foot vents.
5) Turn AIR CONTROL DIAL to
position.
6) Confirm that discharge air comes out of foot vents, with some air from face vents.
7) Turn AIR CONTROL DIAL to
position.
8) Confirm that discharge air comes out of foot vents with some air from defroster vents.
9) Turn AIR CONTROL DIAL to
position.
10) Confirm that all discharge air comes out of defroster vents, with some air from face vents.
3. Check recirculation
1) Switch AIR RECIRCULATION SWITCH to ON position (Indica-tor light ON).
2) Listen for intake door position change (you should hear sound change slightly).
NHA333
NHA334
RHA035E
NHA335
DIAGNOSES Ð Overall System
HA-29
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4. Check temperature decrease
1) Turn TEMPERATURE CONTROL DIAL to full cold (counter-clockwise).
2) Check for cold air at discharge air outlets.
5. Check temperature increase
1) Turn TEMPERATURE CONTROL DIAL to full hot (clockwise).
2) Check for hot air at discharge air outlets.
6. Check A/C switch
Turn FAN CONTROL DIAL to the desired position (1 to 4) and
switch AIR CONDITIONER SWITCH to turn ON air conditioner.
Indicator light will come on when air conditioner is ON.
NHA336
NHA337
NHA338
DIAGNOSES Ð Overall System
Operation Check (Cont'd)
HA-30
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Performance Chart
TEST CONDITION
Testing must be performed as follows:
Vehicle location:Indoors or in the shade (in a well-ventilated place)
Doors: Closed
Door window: Open (Front driver side only)
Hood: Open
TEMP. control dial position: Max. COLD
AIR control dial position:
(Ventilation)
Air recirculation switch position:
(Recirculation)
Fan control dial position: 4
Engine speed: 1,500 rpm
Time required before starting testing
after air conditioner starts operating: More than 10 minutes
TEST READING
Recirculating-to-discharge air temperature table
Inside air (Recirculating air)
at blower assembly inlet Discharge air temperature at center ventilator
ÉC (ÉF)
Relative humidity
% Air temperature
ÉC (ÉF)
40-60 25 (77) 9.8 - 11.5 (50 - 53)
30 (86) 13.8 - 15.9 (57 - 61)
35 (95) 17.9 - 20.3 (64 - 69)
60-80 25 (77) 11.5 - 13.3 (53 - 56)
30 (86) 15.9 - 18.0 (61 - 64)
35 (95) 20.3 - 22.7 (69 - 73)
Ambient air temperature-to-compressor pressure table
Ambient air
High-pressure (Discharge side)
kPa (bar, kg/cm
2, psi) Low-pressure (Suction side)
kPa (bar, kg/cm2, psi)
Relative humidity
% Air temperature
ÉC (ÉF)
40-80 25 (77)
1,451 - 1,608 (14.51 - 16.08,
14.8 - 16.4, 210 - 233) 157 - 186 (1.57 - 1.86, 1.6 - 1.9,
23 - 27)
30 (86) 1,569 - 1,804 (15.69 - 18.04,
16.0 - 18.4, 228 - 262) 176 - 235 (1.76 - 2.35, 1.8 - 2.4,
26 - 34)
35 (95) 1,834 - 2,138 (18.34 - 21.38,
18.7 - 21.8, 266 - 310) 226 - 304 (2.26 - 3.04, 2.3 - 3.1,
33 - 44)
DIAGNOSES Ð Overall System
HA-31
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Performance Test Diagnoses
INSUFFICIENT COOLING
MHA176B
DIAGNOSES Ð Overall System
HA-32
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TROUBLE DIAGNOSES FOR ABNORMAL PRESSURE
Whenever abnormal pressure of high and/or low sides of the system is noted, diagnosis must be conducted
by using a manifold gauge. The large-line zone on the gauge scale (see illustrations.) shown in the following
table refers to the standard (normal) pressure range for the corresponding pressure side (high or low). Since
the standard (normal) pressure, however, differs from vehicle to vehicle, refer to the ªAmbient air temperature-
to-compressor pressure tableº.
Gauge indicationRefrigerant cycleProbable causeCorrective action
Both high- and low-pressure
sides are too high.
AC359A
I Pressure is reduced soon
after water is splashed on
condenser. Excessive refrigerant charge in
refrigeration cycle
Reduce refrigerant until speci-
fied pressure is obtained.
Air suction by radiator or con-
denser fan is insufficient. Insufficient condenser cooling
performance
"
q
1Condenser fins are
clogged.
q
2Improper rotation of radiator
fan or condenser fan I
Clean condenser.
I Check and repair radiator or
condenser fan as necessary.
I Low-pressure pipe is not
cold.
I When compressor is stopped
high-pressure value quickly
drops by approximately 196
kPa (2 kg/cm
2, 28 psi). It
then decreases gradually
thereafter. Poor heat exchange in con-
denser
(After compressor operation
stops, high pressure
decreases too slowly.)
"
Air in refrigeration cycle Evacuate repeatedly and
recharge system.
Engine tends to overheat. Engine cooling systems mal- function.Check and repair each engine
cooling system.
I Areas near low-pressure
pipe connection and service
valves are considerably cold
compared with areas near
expansion valve outlet or
evaporator.
I Plates are sometimes cov-
ered with frost. I
Excessive liquid refrigerant
on low-pressure side
I Excessive refrigerant dis-
charge flow
I Expansion valve is open a
little compared with the
specification.
"
q
1Improper expansion valve
installation
q
2Improper expansion valve
adjustment Replace expansion valve.
DIAGNOSES Ð Overall System
Performance Test Diagnoses (Cont'd)
HA-33
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Gauge indicationRefrigerant cycleProbable causeCorrective action
High-pressure side is too high
and low-pressure side is too low.
AC360A
Upper side of condenser and
high-pressure side are hot,
however, liquid tank is not so
hot. High-pressure tube or parts
located between compressor
and condenser are clogged or
crushed.I
Check and repair or replace
malfunctioning parts.
I Check compressor oil for
contamination.
High-pressure side is too low
and low-pressure side is too
high.
AC356A
High- and low-pressure sides
become equal soon after com-
pressor operation stops. Compressor pressure opera-
tion is improper.
"
Damages inside compressor
packings Replace compressor.
No temperature difference
between high- and low-pres-
sure sides Compressor discharge capac-
ity does not change. (Com-
pressor stroke is set at maxi-
mum.)Replace compressor.
Both high- and low-pressure
sides are too low.
AC353A
I There is a big temperature
difference between liquid
tank outlet and inlet. Outlet
temperature is extremely
low.
I Liquid tank inlet and expan-
sion valve are frosted. Liquid tank inside is clogged a
little.
I
Replace liquid tank
I Check compressor oil for
contamination.
I Temperature of expansion
valve inlet is extremely low
as compared with areas near
liquid tank.
I Expansion valve inlet may
be frosted.
I Temperature difference
occurs somewhere in high-
pressure side High-pressure pipe located
between liquid tank and
expansion valve is clogged.
I
Check and repair malfunc-
tioning parts.
I Check compressor oil for
contamination.
DIAGNOSES Ð Overall System
Performance Test Diagnoses (Cont'd)
HA-34
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Gauge indicationRefrigerant cycleProbable causeCorrective action
Both high- and low-pressure
sides are too low.
AC353A
There is a big temperature dif-
ference between expansion
valve inlet and outlet while the
valve itself is frosted. Expansion valve closes a little
compared with the specifica-
tion.
"
q
1Improper expansion valve
adjustment
q
2Malfunctioning expansion
valve
q
3Outlet and inlet may be
clogged. I
Remove foreign particles by
using compressed air.
I Check compressor oil for
contamination.
I Replace expansion valve.
Areas near low-pressure pipe
connection and service valve
are extremely cold as com-
pared with areas near expan-
sion valve outlet and evapora-
tor. Low-pressure pipe is clogged
or crushed.
I
Check and repair malfunc-
tioning parts.
I Check compressor oil for
contamination.
Air flow volume is not enough
or is too low. Evaporator is frozen.
"
Compressor discharge capac-
ity does not change. (Com-
pressor stroke is set at maxi-
mum length.) Replace compressor.
Low-pressure side sometimes
becomes negative.
AC354A
I Air conditioning system does
not function and does not
cyclically cool the compart-
ment air.
I The system constantly func-
tions for a certain period of
time after compressor is
stopped and restarted. Refrigerant does not discharge
cyclically.
"
Moisture is frozen at expan-
sion valve outlet and inlet. "
Water is mixed with refrigerant. I
Drain water from refrigerant
or replace refrigerant.
I Replace liquid tank.
DIAGNOSES Ð Overall System
Performance Test Diagnoses (Cont'd)
HA-35
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