Step  | Action  | Value(s)  | Yes  | No  | 
|---|---|---|---|---|
1  | Check the vehicle for Diagnostic Trouble Codes (DTCs). Are any DTCs present?  | --  | Go to Diagnostic Trouble Code (DTC) List in Engine Controls  | Go to Step 2  | 
2  | 
 Is the SERVICE ENGINE SOON indicator on?  | --  | Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls  | Go to Step 3  | 
3  | Check for a poor connection or open in CKT 419. Is there a poor connection or an open in CKT 419?  | --  | Go to Step 4  | Go to Step 5  | 
4  | Repair the poor connection or open in CKT 419. Has the repair been made and the system rechecked?  | --  | System OK  | --  | 
5  | 
 Has the repair been made and the system rechecked?  | --  | System OK  | --  |