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Symptom Troubleshooting Index

SYMPTOM TROUBLESHOOTING INDEX

Symptom Diagnostic Procedure
Engine overheats
  1. Inspect the water pump (see WATER PUMP INSPECTION ).
  2. Check the thermostat (see THERMOSTAT TEST ).
  3. Check for any engine coolant leakage (from gaskets, hoses, O-rings, etc.).
  4. Check for dirt, leaves, or insects on radiator and A/C condenser.
  5. Check for a damaged or deformed fan shroud.
  6. Check for plugged or deteriorated radiator hoses.
  7. Check the radiator cap (see RADIATOR CAP TEST ).
  8. Inspect the fan motors (see FAN MOTOR TEST ) or fan relays (see POWER RELAY TEST ).
  9. Check for plugged heater core or hoses.
  10. Check the coolant level.
  11. Check for deteriorated coolant.
  12. Check for a damaged cylinder head gasket.
The radiator fan runs at low speed, but does not run at high speed when the engine coolant temperature is above 206 °F (97 °C) RADIATOR FAN HIGH SPEED CIRCUIT TROUBLESHOOTING  (see ).
With the A/C off and the engine coolant temperature at 206 °F (97 °C) or below, the A/C condenser fan runs at high speed and the radiator fan does not run. When the coolant temperature is above 206 °F (97 °C), both fans run at high speed Remove the fan control relay, and test it.
  • If the relay is faulty, replace it.
  • If the relay is OK, repair a short in the wire between fan control relay 5P socket terminal No. 1 and condenser fan motor 2P connector terminal No. 1.
The radiator fan and the A/C condenser fan run at high speed with the ignition switch ON (II), the A/C off, and the engine coolant temperature below 204 °F (95 °C) Repair a short in the wire between radiator fan relay 4P socket terminal No. 4 and PCM connector terminal A5.
The radiator fan and the A/C condenser fan run at low speed with the ignition switch ON (II) and the A/C off Repair a short in the wire between A/C condenser fan relay 4P socket terminal No. 4 and PCM connector terminal A4.
Both the radiator fan and the A/C condenser fan do not run at low speed with the A/C on Radiator and A/C condenser fans low speed circuit troubleshooting (see RADIATOR AND A/C CONDENSER FAN LOW SPEED CIRCUIT TROUBLESHOOTING ).
The A/C condenser fan does not run at all. The radiator fan does not run at low speed, but it runs at high speed A/C condenser fans high speed circuit troubleshooting (see A/C CONDENSER FAN HIGH SPEED CIRCUIT TROUBLESHOOTING ).
Both the radiator fan and the A/C condenser fan do not run at high speed when the engine coolant temperature is above 206 °F (97 °C) Repair an open in the wire between radiator fan relay 4P socket terminal No. 4 and PCM connector terminal A5.
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