ATC System

For every fault that sets, the A/C - heater control maintains an independent count of the number of key cycles since the active DTC cleared, the odometer reading when the DTC set, and the elapsed ignition on time that the DTC was active. When the number of key cycles (by parameter) reaches a global number, the system automatically clears all of the information associated with that DTC. A loss of battery voltage will also clear all active DTCs and associated data from memory. However, upon reconnecting the battery and activating the A/C - heater control ("Ignition" line going "HIGH"), the system will again evaluate all parameters and will set active DTCs for parameters outside of acceptable limits.

DTCs can also be cleared manually from the A/C - heater control (which also resets key cycle counters). Use a scan tool to clear DTCs stored in the A/C - heater control of the ATC system.