System Diagnostics

Self-diagnostic capabilities of this system, if properly used, can simplify testing. Cruise control system is monitored by Powertrain Control Module (PCM).

If a problem is sensed with a monitored circuit, a trouble code is stored in PCM memory. Once codes are known, see TROUBLE CODES to determine questionable circuit. Test circuits, and repair or replace components as required. If problem is repaired or ceases to exist, PCM cancels that trouble code after 50 ignition on/off cycles. To clear codes, see CLEARING TROUBLE CODES.

A specific trouble code results from a particular system failure. Components in that system are not necessarily the reason for that failure. The trouble code does not condemn a specific component, it indicates a circuit malfunction.