2888341 - D31 ENGINE OVERHEATING / WITH FAN NOT WORKING

The reading on the instrument in the panel shows a high engine coolant temperature and the cooling fan does not come on (Otherwise  See table D30  ENGINE OVERHEATING)
Results of the tests
1CHECK OPERATION OF COOLING FANAll OKProblems metOperation
Connect the test equipment (Examiner or other instruments) to the tester connection and carry out active diagnosis on the engine cooling fan: (in engine management control unit mode)Continue to Step 4Fault in electric fan operationContinue to Step 2
2ELECTRIC FAN CHECKAll OKProblems metOperation
Check the condition and correct operation of the engine cooling fan (e.g. by powering the fan directly from the battery)Continue to Step 3Electric fan faultyReplace electric fan Op.   1088E10 
3FAN OPERATING CIRCUIT CHECKAll OKProblems metOperation

Check, in order:

  • fan fuse
  • fan engagement relay
  • fan resistors
  • connection between engine management control unit and fan relay
  • connection between relay and fan ( See   E5020  ENGINE COOLING )
Continue to Step 4Connections not correctRestore the connections
Component defectiveReplace the component involved (if a fuse is involved, search for the cause of the problem)
Engine management control unit faultyCarry out a thorough check on the control unit (using diagnostic equipment - Examiner or other instruments) and, if necessary, replace the engine control unit
4CHECKING CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persistsSearch for the fault starting from another symptom'