Retrieving Codes Using Scan Tool

Ensure engine is warmed to normal operating temperature. If engine does not start, continue with testing. Turn ignition on. Ensure test equipment is properly attached.
Using the scan tool, 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 ECM.
- Select DTCs.
- Select DIAGNOSTIC TEST MODE RESULTS.
At this point, scan tool should display all DTCs. Write down codes in order displayed. If a communication problem exists between scan tool and ECM, check for loose power and data cables to scan tool.
NOTE: If a DTC is retrieved, ECM may have stored data. See FREEZE FRAME DATA . If desired, check freeze frame data before clearing codes. Clearing codes will erase freeze frame data.
To determine if codes will reappear, indicating a hard (non-intermittent) fault, clear codes and recheck for codes. 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 DRIVE CYCLES .
If one or more DTCs retrieved, service DTCs in order scan tool displayed them. Go to appropriate DTC test. If no DTCs or DTC P0000 (pass code) retrieved, proceed to TESTS W/O CODES article.