Test Description
The numbers below refer to the step numbers in the diagnostic procedures.
- 1 - The Diagnostic System Check - Engine Controls prompts the technician to complete some basic checks and store freeze frame data, if applicable. This creates an electronic copy of data taken when fault occurred. Information is then stored in the scan tool for later reference.
- 2 - This step checks whether the malfunction that caused the DTC P0133 is still present. Operating vehicle in CHECK MODE enhances the diagnostic capabilities of the PCM. HO2S 1 diagnostic can be monitored on the scan tool under I/M SYSTEM INFORMATION. When HO2S test displays a YES status, indicating the heated oxygen sensor system diagnostic is completed, check for a DTC P0133 in LAST TEST FAILED screen of scan tool. If there is no DTC P0133 displayed the HO2S diagnostic has run and passed, indicating no malfunction was present this time. DTCs MUST be cleared to view CURRENT STATUS of system diagnostics being performed. Do not forget the I/M System Information tests only indicates that the test has run, not whether test passed or failed. LAST TEST FAILED screen must be checked for related DTCs to determine the outcome of the diagnostic test involved.
- 5 - In this step, DMM is used as a low current voltage source taking the place of the HO2S. This step verifies whether PCM is able to receive and process a signal from the HO2S 1.