2751148 - Z58 DOWNSTREAM LAMBDA SENSOR SIGNAL ERROR

The diagnostic equipment signals the following error: Downstream Lambda signal
Results of the tests
0PRELIMINARY CHECKSAll OKProblems metOperation
Connect the diagnostic equipment (Examiner or Examiner Plus) and record the errors and environmental parameters.Check for the 'Downstream Lambda signal' error onlyEnd of diagnosisThe 'Upstream Lambda signal' error is presentSee table   Z56 
The 'Mixture strength' error is presentSee table   Z50 
'Misfire' error presentSee table   Z53 
The 'Downstream Lambda signal' and/or 'Catalyzer ' errors are presentContinue to Step 1
Other errors are presentIdentify and eliminate the cause of the problem.Continue to Step 8
1ERROR DETAIL CHECKAll OKProblems metOperation
Check the detail of the 'Downstream Lambda signal' errorIn particular, check that it is not 'Open circuit or short circuit to earth'Continue to Step 3The detail is 'Open circuit or short circuit to earth'Continue to Step 2
2INTAKE AND EXHAUST SYSTEM LEAKAGE CHECKAll OKProblems metOperation
Check the exhaust system visually and by listening In particular, check that there are no leaks from the head outlet to the downstream Lambda sensorContinue to Step 3There are leaksEliminate the leaks from the exhaust system, if necessary, replace the components involved
Engine oil leaks detectedSee table X12
3DOWNSTREAM LAMBDA SENSOR SWITCHING CHECKAll OKProblems metOperation
Use a tester to cancel the errors in the control unit.Road test the vehicle and check the activation of the 2nd closed loop using the diagnostic equipmentContinue to Step 4The activation does not take place (or the signal does not switch)Continue to Step 6
4LAMBDA SENSOR WIRING CHECKAll OKProblems metOperation
Check the downstream Lambda sensor wiring, checking that there are no false contacts See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT Continue to Step 5There are false contactsRestore correct connections. If necessary, replace the defective componentsContinue to Step 8
5ECU SOFTWARE CHECKAll OKProblems metOperation
Check that the engine management control unit software calibration is updatedContinue to Step 8The control unit calibration is not updatedReprogramme the engine management control unit. Continue to Step 8
6LAMBDA SENSOR/ECU INPUT WIRING CHECKAll OKProblems metOperation
Check the wiring for the downstream Lambda sensor input wiring in the ECU, checking that there are no short circuits to the supply or earth, open circuits or false contacts See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT Continue to Step 7There are faulty connectionsRestore correct connections. If necessary, replace the defective components Continue to Step 8
7REPLACING DOWNSTREAM LAMBDA SENSORAll OKProblems metOperation
Replace the downstream Lambda sensor Op. 1080B60Continue to Step 8
8ERROR CANCELLING AND CHECKINGAll OKProblems metOperation
Use a tester to cancel the errors in the control unit.Road test the vehicle and check that the error does not occur againContinue 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 Continue to Step 0
The fault persists, but it is the second time that this step has been reached, or the Lambda sensor has already been replacedContact Technical Support for further information on the problem
9CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosis