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System Operation

SYSTEM OPERATION
The speed control electronic control circuitry is integrated into the Powertrain Control Module (PCM). The PCM is located in the engine compartment. The PCM speed control functions are monitored by the On-Board Diagnostics (OBD). All OBD sensed systems are monitored by the PCM. Each monitored circuit is assigned a Diagnostic Trouble Code (DTC). The PCM will store a DTC in electronic memory for certain failures it detects. See On-Board Diagnostic Test in Powertrain Management/Computer and Control System/Vehicle Speed Control System for more information. The PCM cannot be repaired and must be replaced if faulty.