Central Timer Module: Operation: Notes

The central timer module (CTM) monitors many hard wired switch and sensor inputs as well as those resources it shares with other modules in the vehicle through its communication over the programmable communications interface (PCI) data bus network. The internal programming and all of these inputs allow the CTM to determine the tasks it needs to perform and their priorities, as well as both the standard and optional features that it should provide. The CTM then performs those tasks and provides those features through both PCI data bus communication with other modules and hard wired outputs through a number of driver circuits, relays, and actuators. These outputs allow the CTM the ability to control numerous accessory systems in the vehicle.

The CTM monitors its own internal circuitry as well as many of its input and output circuits, and will store a Diagnostic Trouble Code (DTC) in electronic memory for any failure it detects. These DTCs can be retrieved and diagnosed using a DRBIII(R) scan tool. Refer to the appropriate diagnostic information.