Two versions of the Central Timer Module (CTM) are available on this vehicle, a base version and a high-line version (Central Timer Module). Whichever version of the CTM the vehicle is equipped with, it is concealed behind the trim on the left cowl side inner panel below the instrument panel, where it is secured with three screws. The CTM is enclosed in a molded plastic housing with three integral external connector receptacles that connect it to the vehicle electrical system through one take out and connector of the body wire harness, and two take outs and connectors of the instrument panel wire harness. The base version of the CTM is used on base models of this vehicle. These base models are not equipped with the optional power lock system, the Remote Keyless Entry (RKE) system, the Vehicle Theft Security System (VTSS), or the remote radio controls. The high-line version of the CTM is used on high-line vehicles that are equipped with one or more of those options not found on base models.
The CTM utilizes integrated circuitry and information carried on the Programmable Communications Interface (PCI) data bus network along with many hard wired inputs to monitor many sensor and switch inputs throughout the vehicle. In response to those inputs, the internal circuitry and programming of the CTM allow it to supply the vehicle occupants with audible and visual information, and to control and integrate many electronic functions and features of the vehicle through both hard wired outputs and the transmission of electronic message outputs to other electronic modules in the vehicle over the PCI data bus.
The features that the CTM supports or controls include the following:
Hard wired circuitry connects the CTM to the electrical system of the vehicle. These hard wired circuits are integral to several wire harnesses, which are routed throughout the vehicle and retained by many different methods. These circuits may be connected to each other, to the vehicle electrical system and to the CTM through the use of a combination of soldered splices, splice block connectors, and many different types of wire harness terminal connectors and insulators. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, further details on wire harness routing and retention, as well as pin-out and location views for the various wire harness connectors, splices and grounds.
All versions of the CTM for this model are serviced only as a complete unit. Many of the electronic features in the vehicle controlled or supported by the CTM are programmable using the DRBIII® scan tool. In addition, the CTM software is Flash compatible, which means it can be reprogrammed using Flash reprogramming procedures. However, if any of the CTM hardware components are damaged or faulty, the entire CTM unit must be replaced. The hard wired inputs or outputs of all CTM versions can be diagnosed using conventional diagnostic tools and methods; however, for diagnosis of the CTM or the PCI data bus, the use of a DRBIII® scan tool is required. Refer to the appropriate diagnostic information.