2001 NISSAN PATROL Electronic Repair Manual

4 CHECK COOLING FAN POWER SUPPLY CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect cooling fan relay-1.
SEF690V
3. Turn ignition switch ªONº.
4. Check voltage between cooling fan relay-1 terminals 1, 5 and ground with CONSULT-II or tester.
SEF607X
OK or NG
OKcGO TO 6.
NGcGO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
+Fuse block (J/B) connector E112
+10A fuse or 20A fuse
+30A fusible links
+Harness for open or short between cooling fan relay-1 and fuse
+Harness for open or short between cooling fan relay-1 and battery
cRepair open circuit or short to ground or short to power in harness or connectors.
DTC 0208 OVER HEAT
Diagnostic Procedure (Cont'd)
EC-2012

6 CHECK COOLING FAN GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Disconnect cooling fan motor-1 harness connector.
SEF691V
3. Check harness continuity between cooling fan relay-1 terminal 3 and cooling fan motor-1 terminals 1, 3, cooling fan motor-1 ter-
minals 2, 4 and body ground. Refer to Wiring Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OKcGO TO 7.
NGcRepair open circuit or short to ground or short to power in harness or connectors.
7 CHECK COOLING FAN OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 14 and cooling fan relay-1 terminal 1. Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OKcGO TO 9.
NGcGO TO 8.
8 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E127, M21
+Harness connectors M52, F7
+Harness for open or short between cooling fan relay-1 and ECM
cRepair open circuit or short to ground or short to power in harness or connectors.
9 CHECK COOLING FAN RELAY-1
Refer to ªComponent Inspectionº, EC-2016.
OK or NG
OKcGO TO 10.
NGcReplace cooling fan relay.
DTC 0208 OVER HEAT
Diagnostic Procedure (Cont'd)
EC-2013

10 CHECK COOLING FAN MOTOR-1
Supply battery voltage between the following terminals and check operation.
SEF292Z
OK or NG
OKcGO TO 11.
NGcReplace cooling fan motor.
11 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº.
cINSPECTION END
12 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)
CAUTION:
Higher than the specified pressure may cause radiator damage.
SLC754A
Pressure should not drop.
OK or NG
OKcGO TO 14.
NGcGO TO 13.
13 DETECT MALFUNCTIONING PART
Check the following for leak.
+Hose
+Radiator
+Water pump (Refer to LC section, ªWater Pumpº.)
cRepair or replace.
DTC 0208 OVER HEAT
Diagnostic Procedure (Cont'd)
EC-2014

14 CHECK RADIATOR CAP
Apply pressure to cap with a tester and check radiator cap relief pressure.
SLC755A
Radiator cap relief pressure:
79 - 98 kPa (0.78 - 0.98 bar, 0.8 - 1.0 kg/cm2, 11 - 14 psi)
OK or NG
OKcGO TO 15.
NGcReplace radiator cap.
15 CHECK THERMOSTAT
1. Remove thermostat.
2. Check valve seating condition at normal room temperatures.
It should seat tightly.
3. Check valve opening temperature and valve lift.
SLC343
Valve opening temperature:
82ÉC (180ÉF) [standard] (Models for cold areas)
76.5ÉC (170ÉF) [standard] (Models for except cold areas)
Valve lift:
More than 10 mm/95ÉC (0.394 in/203ÉF)
4. Check if valve is closed at 5ÉC (9ÉF) below valve opening temperature. For details, refer to LC section, ªThermostatº.
OK or NG
OKcGO TO 16.
NGcReplace thermostat.
DTC 0208 OVER HEAT
Diagnostic Procedure (Cont'd)
EC-2015

16 CHECK ENGINE COOLANT TEMPERATURE SENSOR
1. Remove engine coolant temperature sensor.
2. Check resistance between engine coolant temperature sensor terminals 1 and 2 as shown in the figure.
SEF304X
OK or NG
OKcGO TO 17.
NGcReplace engine coolant temperature sensor.
17 CHECK MAIN 12 CAUSES
If the cause cannot be isolated, go to ªMAIN 12 CAUSES OF OVERHEATINGº, EC-2017.
cINSPECTION END
Component Inspection
FUEL PUMP RELAY
Check continuity between terminals 3 and 5.
Conditions Continuity
12V direct current supply between
terminals 1 and 2Yes
No current supply No
If NG, replace relay.SEF145X
DTC 0208 OVER HEAT
Diagnostic Procedure (Cont'd)
EC-2016

Main 12 Causes of Overheating
Engine Step Inspection item Equipment Standard Reference page
OFF 1+Blocked radiator
+Blocked condenser
+Blocked radiator grille
+Blocked bumper+Visual No blocking Ð
2+Coolant mixture+Coolant tester 30 - 50% coolant mixture See ªRECOMMENDED
FLUIDS AND LUBRI-
CANTSº in MA section.
3+Coolant level+Visual Coolant up to MAX level
in reservoir tank and
radiator filler neckSee ªChanging Engine
Coolantº, ªENGINE MAIN-
TENANCEº in MA sec-
tion.
4+Radiator cap+Pressure tester 78 - 98 kPa
(0.78 - 0.98 bar, 0.8 - 1.0
kg/cm
2, 11 - 14 psi)
59 - 98 kPa (0.59 - 0.98
bar, 0.6 - 1.0 kg/cm
2,
9 - 14 psi) (Limit)See ªSystem Checkº,
ªENGINE COOLING SYS-
TEMº in LC section.
ON*2 5+Coolant leaks+Visual No leaks See ªSystem Checkº,
ªENGINE COOLING SYS-
TEMº in LC section.
ON*2 6+Thermostat+Touch the upper and
lower radiator hosesBoth hoses should be hot. See ªThermostatº and
ªRadiatorº, ªENGINE
COOLING SYSTEMº in
LC section.
ON*1 7+Cooling fan+Visual Operating See ªDTC 0208 OVER
HEATº.
OFF 8+Combustion gas leak+Color checker chemical
tester 4 gas analyzerNegative Ð
ON*3 9+Coolant temperature
gauge+Visual Gauge less than 3/4
when drivingÐ
+Coolant overflow to res-
ervoir tank+Visual No overflow during driving
and idlingSee ªChanging Engine
Coolantº, ªENGINE MAIN-
TENANCEº in MA sec-
tion.
OFF*4 10+Coolant return from res-
ervoir tank to radiator+Visual Should be initial level in
reservoir tankSee ªENGINE MAINTE-
NANCEº in MA section.
OFF 11+Cylinder head+Straight gauge feeler
gauge0.1 mm (0.004 in) Maxi-
mum distortion (warping)See ªInspectionº, ªCYLIN-
DER HEADº in EM sec-
tion.
12+Cylinder block and pis-
tons+Visual No scuffing on cylinder
walls or pistonSee ªInspectionº, ªCYLIN-
DER BLOCKº in EM sec-
tion.
*1: Engine running at idle.
*2: Engine running at 3,000 rpm for 10 minutes.
*3: Drive at 90 km/h (55 MPH) for 30 minutes and then let idle for 10 minutes.
*4: After 60 minutes of cool down time.
For more information, refer to ªOVERHEATING CAUSE ANALYSISº in LC section.
DTC 0208 OVER HEAT
EC-2017

Wiring Diagram
TEC187M
DTC 0402 P9zFUEL TEMP SEN
EC-2018

Wiring Diagram
TEC188M
DTC 0403 ACCEL POS SENSOR
EC-2019