Cruise Control Diagnostic System Check

Connect scan tool to Data Link Connector (DLC). DLC is located under left side of instrument panel. If scan tool powers up, go to next step. If scan tool does not power up, diagnose communication system. See TEST B: SCAN TOOL DOES NOT POWER UP under system tests in appropriate BODY CONTROL MODULES article.
Turn ignition switch to RUN position. Using scan tool, attempt to communicate with Powertrain Control Module (PCM). If scan tool communicates with PCM, go to next step. If scan tool does not communicate with PCM, diagnose communication system. See TEST A: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE under SYSTEM TESTS in appropriate BODY CONTROL MODULES article.
Select DISPLAY DTCS function on scan tool for PCM. If scan tool displays DTCs that do not begin with "U", go to next step. If scan tool displays DTCs that begin with "U", diagnose communication system. See TEST A: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE under SYSTEM TESTS in appropriate BODY CONTROL MODULES article.
If scan tool displays DTCs, diagnose appropriate system for DTC retrieved. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If scan tool does not display any DTCs, diagnose by symptom. See SYMPTOM INDEX table under SYSTEM TESTS.