|  |  | Results of the tests | 
| 0 | PRELIMINARY CHECKS | All OK | Problems met | Operation | 
|---|
|  | Connect
the tester (Examiner or Examiner Plus) and transcribe the errors
and environmental parametersCheck for the 'Catalyzer' error only | End of diagnosis | 'Upstream lambda probe' error
present | See
table    Z56 | 
| 'Upstream lambda probe' error present | See table    Z50 | 
| 'Upstream lambda probe' error present | See table    Z53 | 
| 'Upstream lambda probe' error present | See table    Z58 | 
| 'Upstream lambda probe' error present | Continue to Step  1 | 
| 'Upstream lambda probe' error present | Identify and eliminate the cause of the anomaly.Continue
to Step  5 | 
| 1 | EXHAUST SYSTEM LEAKS CHECK | All OK | Problems met | Operation | 
|---|
|  | Look
and listen to check the exhaust system from the cylinder head outlet
to the downstream lambda probe.Check that there are no leaks | Continue to Step 2 | There are leaks | Restore the exhaust system
seal and replace the affected parts if necessaryContinue
to Step  5 | 
| 2 | ROAD TEST TO CHECK MIXTURE STRENGTH | All OK | Problems met | Operation | 
|---|
| 1.2 16v 1.6 16v 2.4 20v | Road test the vehicle and check the mixture strength
in the 1st and 2nd closed loops using the diagnostic equipment.Check that the activation is correct | Continue to Step 3 | The 1st closed loop activation
is not correct | See table    Z56 | 
| The 1st closed loop activation is not correct | See table    Z58 | 
| 1.8 16v | Road test the vehicle and check the mixture strength in
the 1st and 2nd closed loops using the diagnostic equipment.Check that the activation is correct | Continue to Step 3 | The activation is not correct | See table    Z56 | 
| 3 | CHECKING INLET AND EXHAUST SYSTEM
SEAL | All
OK | Problems
met | Operation | 
|---|
|  | Check
the exhaust system visually and by listening, to check that there
are no leaks from the cylinder head outlet to the upstream lambda sensor | Continue to Step 4 | Seal not correct | Restore system seal and replace
the affected parts if necessaryContinue to Step  5 | 
| 4 | REPLACING THE CATALYZER | All OK | Problems met | Operation | 
|---|
|  | Replace
the catalyzer   Op.   1080B62 | Continue to Step 5 |  |  | 
| 5 | DELETING AND CHECKING ERROR | All OK | Problems met | Operation | 
|---|
|  | Use
a tester to cancel the errors in the control unit.Carry out a road test and ensure the error does not recur | Continue to Step 6 | The fault persists, it
is the first time that this step has been reached and the catalyzer
has not yet been replaced | Continue to Step  0 | 
| The fault persists, it is the first time that this step
has been reached and the catalyzer has not yet been replaced | Contact Technical Support for further information on
the problem | 
| 6 | CHECKING  CORRECT OPERATION | All OK | Problems met | Operation | 
|---|
|  | Check
that the fault is no longer present | End of diagnosis |  |  |