Nissan Frontier. Manual - part 215

COOLING SYSTEM

CO-7

< SYSTEM DESCRIPTION >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

CO

N

P

O

SYSTEM DESCRIPTION

COOLING SYSTEM

Cooling Circuit

INFOID:0000000009478158

PBIC3008E

CO-8

< SYSTEM DESCRIPTION >

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COOLING SYSTEM

Schematic

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AWBIA1004GB

OVERHEATING CAUSE ANALYSIS

CO-9

< SYSTEM DESCRIPTION >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

CO

N

P

O

OVERHEATING CAUSE ANALYSIS

Troubleshooting Chart

INFOID:0000000009478160

Symptom

Check items

Cooling sys-
tem parts 
malfunction

Poor heat transfer

Water pump malfunction

Worn or loose drive belt

—

Thermostat or water control 
valve stuck closed

Thermostat or water control 
valve

Damaged fins

Dust contamination or pa-
per clogging

Physical damage

Clogged radiator cooling 
tube

Excess foreign material 
(rust, dirt, sand, etc.)

Reduced air flow

Cooling fan does not oper-
ate

Fan assembly

—

High resistance to fan rota-
tion

Damaged fan blades

Damaged radiator shroud

—

Radiator shroud

—

Improper engine coolant 
mixture ratio

—

Engine coolant viscosity

—

Poor engine coolant quality

—

—

Insufficient engine coolant

Engine coolant leaks

Cooling hose

Loose clamp

Cracked hose

Water pump

Poor sealing

Radiator or reservoir cap

Loose

Poor sealing

O-ring for damage, deterio-
ration or improper fitting

Radiator

Cracked radiator tank

Cracked radiator core

Reservoir tank

Cracked reservoir tank

Overflowing reservoir tank

Exhaust gas leaks into cool-
ing system

Cylinder head deterioration

Cylinder head gasket deteri-
oration

CO-10

< SYSTEM DESCRIPTION >

[QR25DE]

OVERHEATING CAUSE ANALYSIS

Except cool-
ing system 
parts mal-
function

—

Overload on engine

Abusive driving

High engine rpm under no 
load

Driving in low gear for ex-
tended time

Driving at extremely high 
speed

Powertrain system malfunc-
tion

—

Installed improper size 
wheels and tires

Dragging brakes

Improper ignition timing

Blocked or restricted air 
flow

Blocked bumper

Mud contamination or paper 
clogging

—

Blocked radiator grille

Installed car brassiere

Mud contamination or paper 
clogging

Blocked radiator

Blocked air flow

Blocked condenser

Installed large fog lamp

Symptom

Check items