3308610 - D30 ENGINE OVERHEATING / WITH THE FAN WORKING

The reading on the special instrument in the panel shows a high engine coolant temperatureThe cooling fan comes on normally.
Results of the tests
0PRELIMINARY CHECKSAll OKProblems metOperation

First check:

  • engine coolant level
  • engine oil level
  • correct tension of water pump belt
 Continue to Step 1 Low engine coolant level Top up engine coolant level Op. 1088A10
Low engine oil level Top up engine oil level Op.   1084A10 
Tension incorrect Replace the belt Op.   1092G10 
1TEMPERATURE GAUGE OPERATION CHECKAll OKProblems metOperation
Connect diagnostic equipment (Examiner or other instruments) to the diagnostic socket. (in the engine management control unit ambient): read the engine temperature value shown amongst the parameters and compare it with the instrument reading Continue to Step 2 Values do not agree. Instrument reading faulty See table K25 ENGINE COOLANT TEMPERATURE GAUGE NOT WORKING
2CHECK COOLANT TEMPERATURE SENSORAll OKProblems metOperation
Check that the engine coolant temperature sensor is working: See Test   1056BC  Check on operation of engine coolant temperature sensor Continue to Step 3 Sensor faulty Replace temperature sensor Op.   1056B50 
Connections not correctRestore connections
3VISUAL INSPECTION OF CCOLANT EXPANSION TANKAll OKProblems metOperation
Start up the engine and visually check that there are no air bubbles in the expansion tank Continue to Step 4 Air in the cooling circuitEliminate the air from the cooling circuit
4CHECKING CYLINDER HEAD GASKETAll OKProblems metOperation
2.0 TS 2.4 JTD 10v

Verify:

  • that the cylinder head tightening is correct
  • the gasket seal
 Continue to Step 5 Cylinder head tightening not correctRestore correct tightening
Gasket damaged Replace the gasket Op.   1016C11 
2.0 TB 2.5 V6 3.0 V6 2.5 V6 CAE 3.0 V6 CAE

Verify:

  • that the cylinder head tightening is correct
  • the gasket seal
 Continue to Step 5 Cylinder head tightening not correctRestore correct tightening
Gasket damaged Replace the gasket Op.   1016D11 
5CHECK THERMOSTAT UNITAll OKProblems metOperation

Verify:

  • the condition of the thermostat unit
  • that it is correctly calibrated
 Continue to Step 6 Thermostat unit faulty Replace the thermostat unit Op.   1088C40 
6PIPE CHECKAll OKProblems metOperation
Check the condition and seal of the pipes.

In particular:

  • no obstructions
  • condition of hoses, connectors and plugs
 Continue to Step 7 Tightening not correctRestore the correct tightening
Damaged componentsReplaced the damaged components (see Assembly 1088D)
7CHECKING RADIATORAll OKProblems metOperation
Check the condition of the radiator Continue to Step 8 Radiator damaged or distorted Replace the radiator Op.   1088B24 
8WATER PUMP CHECKAll OKProblems metOperation

Check

  • the condition of the water pump
  • the seal of the gaskets
 Continue to Step 9 Water pump faulty Replace the water pump or the gaskets Op.   1088C12 
9HECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persistsSearch for the fault starting from another symptom'