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NO.17 COOLING SYSTEM CONCERNS-OVERHEATING [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513)

BME010300103222

17 | Cooling system concerns-overheating
DESCRIPTION | • Engine runs at higher than normal temperature/overheats.
POSSIBLE CAUSE | • Improper coolant level • Blown fuses • Coolant leakage • Excessive A/C system pressure • Improper water/anti-freeze mixture
• Fans reverse rotation
• Poor radiator condition
• Thermostat malfunction
• Radiator hoses damage
• Condenser fan is inoperative.
• Improper or damaged radiator cap
• Cooling fan is inoperative.
• Coolant overflow system malfunction
• Improper tension of drive belt
• Drive belt damage
• Fan control module 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
  - Overflow system
  - Fan rotational direction
  - Fuses

• Are all items normal?
Yes
Go to the next step.
No | Service if necessary. Repeat Step 1.
2 | • Connect the WDS or equivalent to the DLC-2. • Turn the ignition switch to the ON position (Engine off). • Retrieve any DTCs. • Is "PASSED" displayed? | Yes | No DTC is displayed: • Go to the next step.
No | DTC is displayed: • Go to the applicable DTC inspection. (See DTC TABLE [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513).)
3 | • Start the engine and run it at idle speed. • Turn the A/C switch on. • Does the A/C compressor engage? | Yes | Go to step 5.
No | Inspect the following and repair or replace if necessary: • Refrigerant charging amount • Open circuit between A/C relay and PCM terminal 69 • Seized A/C magnetic clutch • A/C magnetic clutch malfunction

  - If all items are normal, Inspect the following:

  • Refrigerant pressure switch operation
  • Evaporator temperature sensor and A/C amplifier
  • A/C switch is stuck open.
  • Open or short circuit between refrigerant pressure switch and PCM terminal 41
  • Open circuit of blower motor fan switch and resistor (if blower motor does not operate)

4 | • Start the engine and run it at idle speed. • Turn the A/C switch ON. • Do the cooling fan and the condenser fan operate? | Yes | Go to the next step.
No | Cooling fan motor does not operate: • Inspect for the following:

  - Cooling fan motor malfunction
  - Cooling fan motor GND open
  - Open circuit between cooling fan motor and fan control module

Condenser fan motor does not operate:
• Inspect for the following:

  - Condenser fan motor malfunction
  - Condenser fan motor GND open
  - Open circuit between condenser fan motor and fan control module

Both cooling fan and condenser fan do not operate:
• Inspect for the following:

  - Fan control module malfunction
  - Fan control module GND open
  - Open circuit between fan control module and cooling fan relay

5 | • Is the drive belt normal? | Yes | Go to the next step.
No | Replace the drive belt.
6 | • Is there any leakage around heater unit in passenger compartment? | Yes | Inspect and service heater for leakage.
No | Go to the next step.
7 | • Is there any leakage at coolant hoses and/or the radiator? | Yes | Replace the malfunctioning part.
No | Go to the next step.
8 | • Cool down the engine. • Remove the thermostat and inspect the operation. (See THERMOSTAT REMOVAL/INSTALLATION [AJ].) (See THERMOSTAT INSPECTION.) • Is the thermostat normal? | Yes | Engine coolant temperature and the thermostat are normal. Inspect the engine block for leakage or blockage.
No | Access ECT PID on WDS or equivalent. Inspect both ECT PID and the temperature gauge readings. • If the temperature gauge on the instrument cluster indicates normal range but ECT PID is not the same as the temperature gauge reading, inspect the ECT sensor.
• If the temperature gauge on the instrument cluster indicates overheating but ECT PID is normal, inspect the temperature gauge and heat gauge unit.
9 | • Verify test results.

  - If normal, return to diagnostic index to service any additional symptoms.
  - If malfunction remains, inspect related Service Information and perform repair or diagnosis.

  • If vehicle is repaired, troubleshooting completed.
  • If vehicle is not repaired or additional diagnostic information is not available, replace or reprogram the PCM.