KOEO Self-Test (Key On Engine Off)
- 1)
Ensure engine is warmed to normal operating temperature. If engine does not start, continue with KOEO SELF-TEST. Turn ignition switch to OFF position. Ensure test equipment is properly attached.
- 2)
Using the scan tester, select and enter the following data:
- Select vehicle and engine selection menu.
- Select year, engine, model and any additional information requested by scan tool.
- Select DIAGNOSTIC DATA LINK.
- Select PCM - POWERTRAIN CTRL MODULE.
- Select DIAGNOSTIC TEST MODES.
- Select READ/CLEAR DIAGNOSTIC TEST RESULTS.
- Turn ignition on.
- Press trigger on NGS tester and press START button.
- 3)
At this point, scan tool should display all KOEO and continuous DTCs. Write down codes in order displayed. If a communication problem exists between scan tool and PCM, see COMMUNICATION ERROR .
NOTE:
If a DTC is retrieved during QUICK TEST , PCM may have stored PID data. See FREEZE FRAME DATA MODE under ADDITIONAL SYSTEM FEATURES. If desired, check freeze frame data before clearing codes. Clearing codes will erase freeze frame data.
- 4)
To determine if DTCs will reappear, indicating a hard (non-intermittent) fault, clear codes and rerun KOEO SELF-TEST. See CLEARING CODES . If DTC immediately returns, malfunction is considered to be a hard fault. If a DTC does not immediately return, vehicle may need to be driven in a special pattern to cause code to reset. See OBD II-B DRIVE CYCLE MODES .
- 5)
If one or more DTCs were retrieved, refer to DTC REFERENCE CHART under DIAGNOSTIC TROUBLE CODE (DTC) CHART to find proper CIRCUIT TEST to perform. Service DTCs in order scan tool displayed them. If no DTCs are retrieved, proceed to KOER SELF-TEST.