|  |  | Results of the tests | 
| 0 | PRELIMINARY CHECKS | All OK | Problems met | Operation | 
|---|
|  | First
check that the unpleasant smells are not coming from the outside:
they can be eliminated straight away by switching on the recirculation function | Continue to Step 1 | Recirculation not working | See table   L16  CLIMATE CONTROL RECIRCULATION NOT WORKING | 
| 1 | CONDENSATION DRAINAGE PIPE CHECK | All OK | Problems met | Operation | 
|---|
|  | Check
the state of the condensation drainage pipe from the air conditioning
unit: it should not be dirty or obstructed. | Continue to Step 2 | Pipe obstructed | Repair the drainage pipe | 
| 2 | POLLEN FILTER CHECK | All OK | Problems met | Operation | 
|---|
|  | Check
the condition of the pollen filter |  | The pollen filter should be replaced
at least once a year | 
 | Continue to Step 3 | Filter obstructed | Replace the filter element
  Op.   5010B09 | 
| 3 | AIR SUPPLY DUCTS CHECK | All OK | Problems met | Operation | 
|---|
|  | Check
the air supply ducts: they should not be obstructed with dirt or
foul smelling substances | Continue to Step 4 | Obstructed ducts | Clean ducts | 
| 4 | HEATER RADIATOR AND EVAPORATOR
CHECK | All
OK | Problems
met | Operation | 
|---|
|  | Check
the heater radiator and the evaporator: the fins should not be obstructed
with dirt or other substances. | Continue to Step 5 | Radiator dirty or obstructed | Clean or replace the radiator  Op.   5040C50 | 
| Evaporator dirty or obstructed | Clean or replace the evaporator  Op.   5040C64 | 
| 5 | CORRECT OPERATION CHECK | All OK | Problems met | Operation | 
|---|
|  | Check
that the fault is no longer present |  | Fault persists | Search for the fault starting from another symptom' |