Radio, Stereo, and Compact Disc: Description and Operation

AUDIO
An audio system is standard factory-installed equipment on this model, unless the vehicle is ordered with an available radio delete option. Several combinations of radio receivers and speaker systems are offered as optional equipment on this model. The audio system receives fused battery current from a fuse in the Junction Block (JB) at all times. The internal circuitry of the radio permits the radio to operate dependent on a fused 12 volt signal from the ignition switch. The audio system includes the following components:
- Antenna
- Clockspring (with remote radio switches only)
- High-line Central Timer Module (CTM) (with remote radio switches)
- Power amplifier (with premium speaker system only)
- Radio noise suppression components
- Radio receiver
- Remote radio switches (optional)
- Speakers

For complete circuit diagrams, 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 pinout and location views for the various wire harness connectors, splices and grounds.

Refer to the owner's manual for more information on the features, use and operation of each of the available audio systems.

CENTRAL TIMER MODULE
The high-line Central Timer Module (CTM) can also control some features of the audio system when the vehicle is equipped with remote radio switches. A high-line CTM is used on high-line versions of this vehicle. The CTM combines the functions of a chime/ buzzer module, an intermittent wipe module, an illuminated entry module, a remote keyless entry module, and a vehicle theft security system module in a single unit.

The high-line CTM also controls and integrates many of the additional electronic functions and features included on models with this option. The remote radio switch option is one of the features that the CTM controls. The CTM is programmed to send switch status messages over the Programmable Communications Interface (PCI) data bus to control the volume, seek, and pre-set station advance functions of the RAZ radio receiver. The CTM monitors the status of the remote radio switches located on the steering wheel through a hard wired circuit. The CTM then sends the proper switch status messages to the radio receiver. The electronic circuitry within the radio receiver responds to the switch status messages it receives by adjusting the radio settings as requested.

(Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/BODY CONTROL/CENTRAL TIMER MODULE - DESCRIPTION). (Refer to ELECTRICAL/AUDIO/REMOTE SWITCHES - DESCRIPTION). In addition, radio receivers connected to the PCI data bus have several audio system functions that can be diagnosed using a DRB III scan tool. Refer to the proper Diagnostic Procedures manual for more information on DRB III testing of the audio systems.