1998 NISSAN PATROL sensor

OVERALL FUNCTION CHECK
Use this procedure to check the overall function of the cooling fan.
During this check, a DTC might not be con®rmed.
WARNING:
Never remove the radiator cap when the engine is hot. Serious
burns could be caused by high pressure ¯uid escaping from
the radiator.
Wrap a thick cloth around the cap. Carefully remove the cap
by turning it a quarter turn to allow built-up pressure to
escape. Then turn the cap all the way off.
1) Check the coolant level in the reservoir tank and radiator.
Allow engine to cool before checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to ``DIAG-
NOSTIC PROCEDURE'', EC-117.
2) Con®rm whether customer ®lled the coolant or not. If customer
®lled the coolant, skip the following steps and go to ``DIAGNOS-
TIC PROCEDURE'', EC-117.
3) Turn ignition switch ``ON''.
4) Perform ``COOLING FAN'' in ``ACTIVE TEST'' mode with
CONSULT and make sure that cooling fan operates
when touching ``ON''.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------OR-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
3) Disconnect engine coolant temperature sensor harness
connector.
4) Connect 150Wresistor to engine coolant temperature
sensor harness connector.
5) Start engine and make sure that cooling fan operates.
Be careful not to overheat engine.
AEC640
SEF758V
SEF979S
TROUBLE DIAGNOSIS FOR ``OVER HEAT'' (DTC 28)
Cooling Fan (Overheat) (Cont'd)
EC-115

DIAGNOSTIC PROCEDURE
INSPECTION START
CHECK COOLING FAN OPERATION.
1. Turn ignition switch ``OFF''.
2. Turn ignition switch ``ON''.
3. Perform ``COOLING FAN'' in
``ACTIVE TEST'' mode with
CONSULT and make sure that
cooling fan operates when touch-
ing ``ON''.
--------------------------------------------------------------------------------------------------------------------------------------OR--------------------------------------------------------------------------------------------------------------------------------------
2. Disconnect engine coolant tem-
perature sensor harness connec-
tor.
3. Connect 150Wresistor to engine
coolant temperature sensor har-
ness connector.
4. Start engine and make sure that
cooling fan operates.
NG
cOK
Go to``CHECK COOL-
ING SYSTEM FOR LEAK'',
EC-119.
CHECK POWER SUPPLY.
1. Turn ignition switch ``OFF''.
2. Disconnect cooling fan relay-1.
3. Turn ignition switch ``ON''.
4. Check voltage between terminals
V2,
V5and ground with CONSULT or tester.
Voltage: Battery voltage
OK
cNG
Check the following.
+10A fuse
+30A fusible link
+Harness for open or short
between cooling fan
relay-1 and fuse
+Harness for open or short
between cooling fan
relay-1 and battery
If NG, repair harness or
connectors.
CHECK GROUND CIRCUIT.
1. Turn ignition switch ``OFF''.
2. Disconnect cooling fan motor harness
connector.
3. Check harness continuity between
relay terminal
V3and motor termi-
nals
V1,V3.
Continuity should exist.
If OK, check harness for short to
ground and short to power.
4. Check harness continuity between
motor terminals
V2,V4and body
ground.
Continuity should exist.
If OK, check harness for short to
ground and short to power.
OK
cNG
Repair open circuit or short
to ground or short to power
in harness or connectors.
jA
SEF758V
SEF979S
SEF690V
SEF759V
SEF691V
.
.
.
.
TROUBLE DIAGNOSIS FOR ``OVER HEAT'' (DTC 28)
Cooling Fan (Overheat) (Cont'd)
EC-117

CHECK COOLING SYSTEM FOR LEAK.
Apply pressure to the cooling system with
a tester, and check if the pressure drops.
Testing pressure:
157 kPa (1.57 bar, 1.6 kg/cm
2, 23 psi)
Pressure should not drop.
CAUTION:
Higher than the speci®ed pressure may
cause radiator damage.
OK
cNG
Check the following for
leak.
+Hose
+Radiator
+Water pump
Refer to LC section (``Water
Pump'').
CHECK RADIATOR CAP.
Apply pressure to cap with a tester.
Radiator cap relief pressure:
78 - 98 kPa (0.78 - 0.98 bar, 0.8 - 1.0
kg/cm
2, 11 - 14 psi)
OK
cNG
Replace radiator cap.
CHECK THERMOSTAT.
1. Check valve seating condition at normal
room temperatures.
It should seat tightly.
2. Check valve opening temperature and
valve lift.
Valve opening temperature:
82ÉC (180ÉF) [standard]
Maximum valve lift:
More than 10 mm/95ÉC
(0.39 in/203ÉF)
3. Check if valve is closed at 5ÉC (9ÉF)
below valve opening temperature.
For details, refer to LC section (``Thermo-
stat'').
OK
cNG
Replace thermostat.
Check engine coolant temperature sensor.
Refer to ``COMPONENT INSPECTION'',
EC-82.
OK
cNG
Replace engine coolant
temperature sensor.
If the cause cannot be isolated, go to
``MAIN 12 CAUSES OF OVERHEATING''
on next page.
INSPECTION END
Perform FINAL CHECK by the following procedure after repair
is completed.
1. Warm up engine. Run the vehicle for at least 20 minutes. Pay
attention to engine coolant temperature gauge on the instrument
panel. If the reading shows an abnormally high temperature,
another part may be malfunctioning.
2. Stop vehicle and let engine idle. Check the intake and exhaust
systems for leaks by listening for noise or visually inspecting the
components.
3. Allow engine to cool and visually check for oil and coolant leaks.
Then, perform ``OVERALL FUNCTION CHECK''.
SLC754AA
SLC755AB
SLC343
.
.
.
.
.
TROUBLE DIAGNOSIS FOR ``OVER HEAT'' (DTC 28)
Cooling Fan (Overheat) (Cont'd)
EC-119

Charge Air Temperature Sensor
The charge air temperature sensor is used to detect the charge air
temperature. The sensor modi®es a voltage signal from the ECM.
The modi®ed signal returns to the ECM as the charge air tempera-
ture input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.
The ECM uses this signal for the charge air cooler control.

Charge air temperatureÉC (ÉF) Voltage
(V) Resistance
(kW)
þ10 (14) 4.4 7.0 - 11.4 20 (68) 3.5 2.1 - 2.9
50 (122) 2.3 0.68 - 1.00
90 (194) 1.0 0.236 - 0.260
110 (230) 0.64 0.143 - 0.153
150 (302) 0.30 0.050 - 0.065
ECM TERMINALS AND REFERENCE VALUE
Remarks: Speci®cation data are reference values and are measured between each terminal andV43(ECCS
ground) with a voltmeter.
TER-
MINAL NO. WIRE
COLOR ITEM CONDITION DATA
(DC Voltage and Pulse Signal)
36 LG Charge air temperature
sensor Engine is running.
Approximatel
y 0 - 4.8V
Output voltage varies with
charge air temperature.
50 B Sensors' ground Engine is running.
(Warm-up condition)
Idle speed Approximately 0V
ON BOARD DIAGNOSIS LOGIC
Diagnostic
Trouble Code No. Malfunction is detected when ...
Check Items
(Possible Cause)
33 *1 +An excessively high or low voltage from the sensor is
entered to ECM. +
Harness or connectors
(The sensor circuit is open or shorted.)
+ Charge air temperature sensor
*1: When nothing is displayed or the meaningless symbol is displayed in the ``Self-diag result'' mode with CONSULT, perform ``Diagnostic Test Mode II
(Self-diagnostic results)'' with ECM. Refer to EC-32.
DIAGNOSTIC TROUBLE CODE CONFIRMATION
PROCEDURE
1) Turn ignition switch ``ON'' and wait at least 5 seconds.
2) Turn ignition switch ``OFF'', wait at least 5 seconds and then turn ``ON''.
3) Perform ``Diagnostic Test Mode II (Self-diagnostic results)'' with ECM.
SEF594K
SEF012P
TROUBLE DIAGNOSIS FOR ``I/C INT/A TEMP SEN'' (DTC 33)
EC-122

TEC438
TROUBLE DIAGNOSIS FOR ``I/C INT/A TEMP SEN'' (DTC 33)
Charge Air Temperature Sensor (Cont'd)
EC-123

DIAGNOSTIC PROCEDURE
INSPECTION START
CHECK POWER SUPPLY.
1. Turn ignition switch ``OFF''.
2. Disconnect charge air temperature sen-
sor harness connector.
3. Turn ignition switch ``ON''.
4. Check voltage between terminal
V2
and ground with CONSULT or tester.
Voltage:
Approximately 5V
OK
cNG
Repair harness or connec-
tors.
CHECK GROUND CIRCUIT.
1. Turn ignition switch ``OFF''.
2. Check harness continuity between ter-
minal
V1and engine ground.
Continuity should exist.
If OK, check harness for short to
ground and short to power.
OK
cNG
Check the following.
+Harness connectors
F6,M51
+Harness connectors
M88,E106
+Harness for open or
short between ECM and
charge air temperature
sensor
+Harness for open or
short between TCM and
charge air temperature
sensor
If NG, repair open circuit or
short to ground or short to
power in harness or con-
nectors.
CHECK COMPONENT
(Charge air temperature sensor).
Refer to ``COMPONENT INSPECTION''
on next page.
OK
cNG
Replace charge air tem-
perature sensor.
Disconnect and reconnect harness con-
nectors in the circuit. Then retest.
Trouble is not ®xed.
Check ECM pin terminals for damage and
check the connection of ECM harness
connector. Reconnect ECM harness con-
nector and retest.
INSPECTION END
SEF710V
SEF764V
SEF765V
.
.
.
.
.
.
TROUBLE DIAGNOSIS FOR ``I/C INT/A TEMP SEN'' (DTC 33)
Charge Air Temperature Sensor (Cont'd)
EC-124

COMPONENT INSPECTION
Charge air temperature sensor
Check resistance as shown in the ®gure.
Temperature ÉC (ÉF) Resistance kW
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.0
90 (194) 0.236 - 0.260
If NG, replace charge air temperature sensor.
SEF152P
SEF012P
TROUBLE DIAGNOSIS FOR ``I/C INT/A TEMP SEN'' (DTC 33)
Charge Air Temperature Sensor (Cont'd)
EC-125

Needle Lift Sensor (NLS)
The needle lift sensor is built into the No. 1 injection nozzle. Its
piezoelectric element senses changes in fuel injection timing
caused by fuel temperature, etc. This change of fuel injection tim-
ing is sent as a pulse signal to the ECM.
ECM TERMINALS AND REFERENCE VALUE
Remarks: Speci®cation data are reference values and are measured between each terminal andV43(ECCS
ground) with a voltmeter.
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse
Signal)
34 W Needle lift sensorEngine is running.
(Warm-up condition)
Idle speedApproximately 0V
SEF718V
Engine is running.(Warm-up condition)
Engine speed is 2,000 rpm.Approximately 0V
SEF719V
ON BOARD DIAGNOSIS LOGIC
Diagnostic
Trouble Code
No.Malfunction is detected when ....Check Items
(Possible Cause)
34+An improper signal from the sensor is sent to ECM.+Harness or connectors
(The sensor circuit is open or shorted.)
+Needle lift sensor
+Air in fuel line
+Clogging No. 1 injection nozzle
SEF604S
Terminal
Piezoelectric element
TROUBLE DIAGNOSIS FOR ``NEEDLE LIFT SEN'' (DTC 34)
EC-126