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:
- Automatic Door Lock - The high-line CTM provides an automatic door lock feature (also known as rolling door locks). This is a programmable feature.
- Battery Protection - The CTM provides a battery saver feature that performs timed load shedding whenever courtesy, reading, visor vanity, center console, glove box, cargo lamps, or any exterior lamps are left on with the ignition switch in the Off position.
- Central Locking - The high-line CTM on vehicles equipped with the optional Vehicle Theft Security System (VTSS) includes a central locking/unlocking feature.
- Chimes - All versions of the CTM provide chime service and beep request service through an integral chime tone generator.
- Door Lock Inhibit - The high-line CTM provides a power door lock inhibit feature.
- Enhanced Accident Response - The high-line CTM provides an optional enhanced accident response feature. This is a programmable feature.
- Exterior Light Features - The CTM provides control of park lamps, fog lamps, and headlamps. This includes support for optical horn (also known as flash-to-pass), headlamp time delay, cargo lamps, daytime running lamps (DRL - Canada only), and battery saver features.
- Interior Light Features - The CTM provides control of courtesy lamps and dome lamps. This includes support for a timed illuminated entry with fade-to-off, interior lighting delay, courtesy illumination defeat, and battery saver features.
- Intermittent Wipe Control - The CTM provides control of the intermittent wipe delay, and wipe-after-wash features for the wiper and washer system.
- Panic Mode - The high-line CTM provides support for the optional RKE system panic mode including horn chirp, headlamp flash, and park lamp flash features.
- Power Lock Control - The high-line CTM provides the optional power lock system features, including support for the automatic door lock and door lock inhibit modes.
- Programmable Features - The CTM provides support for certain programmable features.
- Remote Keyless Entry - The high-line CTM provides the optional Remote Keyless Entry (RKE) system features, including support for the RKE Lock (with optional horn chirp and park lamps flash), Unlock (with optional park lamps flash), Panic, and illuminated entry modes, as well as the ability to be programmed to recognize up to four RKE transmitters. The RKE horn chirp, park lamps flash features are programmable. On quad cab models only, a driver-door-only unlock or unlock-all-doors feature is also programmable.
- Remote Radio Switch Interface - The high-line CTM monitors and transmits the status of the optional remote radio switches on the steering wheel.
- Speed Sensitive Intermittent Wipe Control - The CTM provides a speed sensitive intermittent wipe feature.
- Vehicle Theft Security System - The high-line CTM provides control of the optional Vehicle Theft Security System (VTSS) features, including support for the central locking/unlocking mode and control of the Security indicator in the instrument cluster.
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.