3233226 - 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 tester (Examiner or other instruments) and transcribe the errors and environmental parametersCheck for the 'Downstream Lambda signal' error onlyEnd of diagnosis'Upstream lambda probe' error present See table   Z56  UPSTREAM LAMBDA SENSOR SIGNAL ERROR
'Mixture concentration' error present See table   Z50  MIXTURE STRENGTH ERROR
The 'Misfire' error is present See table   Z53  MISFIRE ERROR
Only the 'Downstream Lambda signal' and/or 'Catalyzer ' errors are present Continue to Step 1
Other errors presentIdentify and eliminate the cause of the problem Continue to Step 8
1ERROR DETAIL CHECKAll OKProblems metOperation
2.5 V6 Euro 3Check the detail of the 'Downstream Lambda signal' errorIn particular check that it is not 'Signal not valid/Below minimum threshold' Continue to Step 3 The detail is 'Signal not valid/Below minimum threshold' with error P0136 and/or P0156 Continue to Step 2
1.6 TS 1.8 TS [d] Euro 3Check the detail of the 'Downstream Lambda signal' errorIn particular check that it is not 'Signal not valid/Below minimum threshold' Continue to Step 3 The detail is 'Signal not valid/Below minimum threshold' with error P0136 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 sensor Continue to Step 3 Leaks are presentEliminate the leaks from the exhaust system, if necessary, replace the components involved
3DOWNSTREAM LAMBDA SENSOR SWITCHING CHECKAll OKProblems metOperation
Use a tester to cancel the errors in the control unitRoad test the vehicle and check from the diagnostic instrument the activation of the 2nd loop mixture strength check Continue to Step 4 The 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 5 There are false contactsRestore correct connections.If necessary, replace the defective components Continue to Step 8
5ECU SOFTWARE CHECKAll OKProblems metOperation
Check that the engine management control unit software calibration is updated Continue to Step 8 The 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 7 There 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 Continue to Step 8 -
8DELETING AND CHECKING ERRORAll OKProblems metOperation
Use a tester to cancel the errors in the control unitCarry out a road test and ensure the error does not recur Continue to Step 9 The 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
9CHECKING CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persistsSearch for the fault starting from another symptom'