NO.13 COOLING SYSTEM CONCERNS-OVERHEATING [WL-3]

id0103b5913300

13
Cooling system concerns-overheating
DESCRIPTION
•  The engine runs at higher than normal temperature/overheats.
POSSIBLE CAUSE
•  Cooling fan malfunction
•  Low drive belt tension
•  Drive belt damage
•  Improper coolant level
•  Thermostat malfunction
•  Radiator clogging
•  Improper water/anti-freeze mixture
•  Improper or damaged radiator cap
•  Radiator hose damage
•  Coolant leakage (engine internal, turbocharger, external)
•  A/C system malfunction
•  EGR system malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
•  Inspect the following:
―  Engine coolant level
―  Coolant leakage
―  Water and anti-freeze mixture
―  Radiator condition
―  Collapsed or restricted radiator hoses
―  Radiator pressure cap
―  Drive belt tension
―  Drive belt
―  Fan rotational direction
―  Cooling fan
•  Are the all items normal?
Yes
Go to the next step.
No
Service if necessary.
Repeat Step 1.
2
•  Connect the M-MDS to the DLC.
•  Turn the engine switch to the ON position (Engine off).
•  Retrieve any DTCs.
•  Is the DTC displayed?
Yes
DTC is displayed:
•  Go to the appropriate DTC test.
No
No DTC is displayed:
•  Go to the next step.
3
Note
•  The following test should be performed on vehicles with the A/C system. Go to Step 4 for vehicles without the A/C system.
•  Start the engine and run it at idle speed.
•  Turn the A/C switch off.
•  Does the A/C compressor disengage?
Yes
Go to the next step.
No
Go to symptom troubleshooting "NO.19 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY."
4
•  Is the drive belt normal?
Yes
Go to the next step.
No
Replace the drive belt.
5
•  Is there any leakage around heater unit in the passenger compartment?
Yes
Inspect and service heater for leakage.
No
Go to the next step.
6
•  Is there any leakage at the coolant hoses and/or radiator?
Yes
Replace malfunctioning parts.
No
Go to the next step.
7
•  Perform the EGR system inspection.
•  Is the EGR system normal?
Yes
Go to the next step.
No
Inspect the following:
•  EGR solenoid (vent)
•  EGR solenoid (vacuum)
•  EGR valve
•  Vacuum hose connections
•  Wiring harness between EGR solenoid and PCM terminals
Repair or replace if necessary.
8
•  Cool down the engine.
•  Remove the thermostat and inspect the operation.
•  Is the thermostat normal?
Yes
Thermostat is normal.
Inspect cylinder block for leakage or blockage.
No
Replace the thermostat.
9
•  Verify the test results. If normal, return to the diagnostic index to service any additional symptoms.