Powertrain Diagnostic System Check

The powertrain diagnostic system check determines:

If Malfunction Indicator Light (MIL) operates.
If VCM is operating and can recognize a fault.
If any DTCs are stored.

NOTE: Check for applicable Technical Service Bulletins (TSB) before proceeding. Perform the following procedure only if a driveability complaint exists, or if you were sent here from another procedure or article. DO NOT turn ignition off during the following procedure or clear DTCs unless instructed to do so.

Install scan tool. If scan tool powers-up, go to next step. If scan tool does not power-up, see TEST A: SCAN TOOL DOES NOT POWER-UP under SYSTEM TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
Turn ignition on, engine off. Attempt to establish communication with PCM, Vehicle Theft Deterrent (VTD) module, Instrument Panel Cluster (IPC), Electronic Brake And Traction Control Module (EBCM), and HVAC. If scan tool communicates with all listed control modules, go to next step. If scan tool does not communicate with all listed modules, see TEST B: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS II DEVICE under SYSTEM TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
Attempt to start engine. If engine starts and idles, go to next step. If engine cranks, but does not start, see NO-START DIAGNOSIS in appropriate BASIC DIAGNOSTIC PROCEDURES article.
Select DTC display function for PCM, VTD, IPC, EBCM and HVAC. If scan tool displays any DTCs, go to next step. If scan tool does not display any DTCs, go to step 8.
Using scan tool, save or capture powertrain DTC information. After saving information, go to next step.
If scan tool displays any DTCs which begin with "U", see SCAN TOOL DOES NOT COMMUNICATE WITH CLASS II DEVICE under SYSTEM TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT. If scan tool does not display any DTCs which begin with "U", go to next step.
If scan tool displays any DTCs which begin with "P", see DIAGNOSTIC TROUBLE CODE DEFINITIONS .
If concern is with A/T, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS. If concern is not with A/T, go to next step.
If concern is with Inspection/Maintenance (I/M) testing, see INSPECTION/MAINTENANCE PROCEDURES . If concern is not with I/M testing, see appropriate test in appropriate TROUBLE SHOOTING - NO CODES article.