125000736 - Z56 UPSTREAM LAMBDA SENSOR SIGNAL ERROR

The diagnostic equipment signals the following error: Upstream lambda signal
Results of the tests
0PRELIMINARY CHECKSAll OKProblems encounteredOperation
Connect the diagnostic equipment (Examiner or Examiner Plus) and check the errors and environmental parameters.Check that there is only the upstream Lambda signal errorEnd of diagnosisIf only the upstream Lambda signal error, Mixture strength, Misfire, Catalyzer and/or Downstream Lambda signal is presentMove on to Step 1
Other errors presentIdentify and eliminate the cause of the problem.Move on to Step 8
1ERROR DETAIL CHECKAll OKProblems encounteredOperation
Check the upstream Lambda signal error detailIn particular, check that it is not invalid/below minimum level signalMove on to Step 3The detail is above the upper limit with error P0133, P0153, P0139, P0159, P1133 and/or P1153Continue as indicated inSee table    See table Z57 UPSTREAM LAMBDA SENSOR SIGNAL ERROR
The detail is below the lower limitContinue as indicated inSee table    See table Z57 UPSTREAM LAMBDA SENSOR SIGNAL ERROR
The detail is invalid/below minimum level signalMove on to Step 2
2INTAKE AND EXHAUST SYSTEM SEAL CHECKAll OKProblems encounteredOperation
Check the exhaust system by looking and listening. In particular, check that there are no leaks before the upstream Lambda sensorMove on to Step 3There are leaksRestore the correct seal for the exhaust system, if necessary, replace the components involved
3UPSTREAM LAMBDA SENSOR SWITCHING CHECKAll OKProblems encounteredOperation
Using the diagnostic equipment, cancel the errors in the control unit.Start up the engine, let it warm up and, using the diagnostic equipment, check the activation of the 1st loop mixture strength check (or, alternatively the upstream Lambda signal switching)Move on to Step 4The activation does not take place (or the signal does not switch)Move on to Step 6
4LAMBDA SENSOR WIRING CHECKAll OKProblems encounteredOperation
Check the upstream Lambda sensor wiring, checking that there are no false contacts See    See E5030 PETROL ENGINE ELECTRONIC MANAGEMENTMove on to Step 5There are false contactsRestore the correct connections. If necessary, replace the defective components.Move on to Step 8
5ECU SOFTWARE CHECKAll OKProblems encounteredOperation
Check, using FIAT documentation, for the existence of updated engine management software calibrationMove on to Step 8There is no updated software calibration for the control unitReprogramme the engine management control unit.Move on to Step 8
6LAMBDA SENSOR/ECU INPUT WIRING CHECKAll OKProblems encounteredOperation
Check the wiring for the ECU upstream Lambda sensor input circuit, checking that there are no short circuits to earth, open circuits or false contacts See    See E5030 PETROL ENGINE ELECTRONIC MANAGEMENTMove on to Step 7There are faulty connectionsRestore the correct connections. If necessary, replace the defective components.Move on to Step 8
7UPSTREAM LAMBDA SENSOR REPLACEMENTAll OKProblems encounteredOperation
Replace the upstream Lambda sensorsMove on to Step 8.
8ERROR CANCELLING AND CHECKAll OKProblems encounteredOperation
Using the diagnostic equipment, cancel the errors in the control unit.Road test the vehicle and check that the errror does not occur againMove on to Step 9The fault persists, it is the first time that this Step has been reached and the Lambda sensor has not yet been replaced
The fault persists, but it is the second time that this Step has been reached or the Lambda sensor has already been replacedContact the Service Department for further information on the problem
9CHECK ON CORRECT OPERATIONAll OKProblems encounteredOperation
Check that the fault is no longer presentEnd of diagnosis.