On-Board Diagnostic (OBD) System Check: 3.5L

NOTE: Check for applicable Technical Service Bulletins (TSBs) before proceeding. DO NOT perform the following procedure if driveability conditions are not present. DO NOT turn ignition off during the following procedure or clear DTCs unless instructed to do so.

Check if MIL is illuminated with engine running. Check for driveability concerns. Also, check for faulty computer-controlled components. If a problem is found, go to next step. If no problems are found, system is okay.
Turn ignition off. Connect scan tool. Turn ignition on. If scan tool displays PCM data, go to next step. If scan tool does not display PCM data, go to DLC DIAGNOSIS OR NO SCAN TOOL DATA .
Check starter operation. If starter is inoperative, or starter operates with ignition on, diagnose starter circuit. See appropriate wiring diagram in WIRING DIAGRAMS article. If starter operates okay, go to next step.
Attempt to start engine. If engine starts and continues to run, go to next step. If engine does not start, or starts and stalls, go to NO START DIAGNOSIS in appropriate BASIC DIAGNOSTIC PROCEDURES article.
Using scan tool, observe DTC status for MIL REQUEST, FAIL THIS IGN, LAST TEST FAIL and HISTORY. If any DTCs are stored, go to next step. If DTCs are not present, go to step 7.
Using scan tool, save freeze frame and failure records information using scan tool CAPTURE INFO feature. Diagnose DTCs. See DIAGNOSTIC TESTS in appropriate TESTS W/CODES article.
Using scan tool, command MIL on and off. If MIL turns on and off as commanded, go to next step. If MIL does not turn on and off as commanded, check MIL circuit. See appropriate wiring diagram in WIRING DIAGRAMS article.
Compare PCM data values displayed on scan tool with typical control system data values. If values are within limits, go to appropriate TROUBLE SHOOTING - NO CODES article. If values are not within limits, see appropriate SYSTEM & COMPONENT TESTING article.