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AUDIO SYSTEMAn audio system is standard factory-installed equipment on this model, unless the vehicle is ordered with an available radio delete option. Several combinations of radios and speaker systems are offered as factory-installed optional equipment. (Refer to AUDIO/RADIO - DESCRIPTION) and (Refer to AUDIO/SPEAKER - DESCRIPTION). The standard equipment audio system includes an AM/FM/cassette (RAS sales code) stereo radio, and speakers in four locations.
Fig.1 Audio System:
The audio system includes the following major components, which are described in further detail elsewhere in this service information:
- Amplifier - On models equipped with the optional premium speaker system, an audio power amplifier is located on the rear floor panel underneath the left end of the rear seat cushion in the passenger compartment.
- Antenna Body and Cable - The most visible component of the antenna body and cable are the antenna adapter and the antenna cap nut, which are located on the top of the right front fender panel of the vehicle, near the right end of the cowl plenum.
- Antenna Mast - The antenna mast is a metal rod that extends upward from the antenna body and cable on the top of the right front fender panel of the vehicle, near the right end of the cowl plenum.
- Radio - The radio for this model is located in the instrument panel center stack area, inboard of the instrument cluster and above the heater and air conditioner controls.
- Radio Noise Suppression Ground Strap - A radio noise suppression ground strap is installed between the rear of the engine cylinder head and the dash panel sheet metal in the engine compartment.
- Speaker - The standard speaker system includes four speakers in four locations, while the premium speaker system includes six speakers in six locations.
Hard wired circuitry connects the audio system components to each other through 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 audio system components through the use of a combination of soldered splices, splice block connectors and many different types of wire harness terminal connectors and insulators.
The audio system components are designed to provide audio entertainment and information through the reception, tuning and amplification of locally broadcast radio signals in both the Amplitude Modulating (AM) and Frequency Modulating (FM) commercial frequency ranges. Electromagnetic radio signals that are broadcast from a radio station induce electrical modulations into the audio system antenna mast. The antenna body and cable conduct these weak signals from the antenna mast to the radio. The radio then tunes and amplifies these weak signals into stronger electrical signals that are required in order to operate the audio system speakers. The speakers convert these electrical signals into air movement, which reproduces the sounds being broadcast by the radio station.
Some audio systems also offer the user the option of selecting from and listening to prerecorded audio cassette tapes, audio compact discs, or both. Regardless of the media type, the audio system components provide the user with the ability to electronically amplify and adjust the audio signals being reproduced by the speakers within the vehicle to suit the preferences of the vehicle occupants.
The audio system components operate on battery current received through a fuse in the Junction Block (JB) on a fused ignition switch output (run-acc) circuit so that the system will only operate when the ignition switch is in the ON or Accessory positions. See the owner's manual in the vehicle glove box for more information on the features, use and operation of each of the available audio systems.
Fig.2 Amplifier:
AMPLIFIER
The optional Infinity premium speaker system includes a separate Infinity audio power amplifier. This Infinity amplifier is a four channel unit rated at 25 watts per channel, or a total rated output of 100 watts. The amplifier unit is located on the rear floor panel underneath the left end of the rear seat cushion in the passenger compartment. The amplifier unit can be accessed by pulling the rear seat cushion release strap and folding the rear seat cushion forward against the backs of the two front bucket seats. The amplifier is secured to the rear floor panel with three mounting screws, which are installed from the passenger compartment side of the rear floor panel.
The amplifier circuitry is housed within a black painted, extruded aluminum housing with external ribbing. The amplifier housing is designed to aid in the dissipation of heat that is generated by the amplifier circuitry during normal operation. Four integral mounting brackets are used to support the amplifier, two located at the rear side of the housing and two located on the front side. The front inboard mounting bracket features a rubber bumper that rests against the rear floor panel when the amplifier is installed. The remaining three mounting brackets are each secured with a screw to the rear floor panel.
The Infinity audio power amplifier cannot be adjusted or repaired. If damaged or faulty, the entire amplifier unit must be replaced.
The audio power amplifier electronically increases the frequency response of the normal audio signal output from the radio amplifier in order to improve the acoustic performance of the speakers within the vehicle. On vehicles equipped with the audio power amplifier, the amplifier of the radio becomes a pre-amplifier.
All of the amplifier inputs and outputs are connected to two take outs and connectors of the body wire harness on the left side of the vehicle through two connector receptacles located on the left end of the amplifier housing. The amplifier receives battery current through a fuse in the Power Distribution Center (PDC) at all times on two separate fused B(+) circuits. The amplifier is grounded through two separate ground circuits and take outs of the body wire harness on the left side of the vehicle. These two take outs have a single eyelet terminal connector secured by a ground screw to the top of the rear seat riser located on the rear floor panel, just forward of the mounted amplifier. The internal circuitry of the amplifier switches the unit ON or OFF based upon a signal controlled by the radio power switch. The amplifier receives this signal through the radio 12 V output circuit that is energized whenever the radio power switch is turned ON.
The amplifier receives audio signal inputs for four speaker channels from the radio, then sends amplified audio outputs through four separate channels with dedicated feed (+) and return (-) circuits to the six individual speakers. A front door tweeter and a front door speaker each share their respective amplified left or right front channel outputs from the amplifier. The front door tweeter and speaker are connected in parallel, using circuit splices to connect their respective right or left channel feed (+) and return (-) circuitry. Refer to the appropriate wiring information for complete premium audio system wiring diagrams.
Fig.5 Antenna Body And Cable:
ANTENNA BODY & CABLE
The antenna body and cable are not readily visible in their installed positions in the vehicle. The most visible component of the antenna body and cable are the antenna adapter and the antenna cap nut, which are located on the top of the right front fender panel of the vehicle, near the right end of the cowl plenum. The antenna body and cable are secured below the fender panel by the antenna cap nut through a prefabricated and dedicated mounting hole in the top of the right front fender. The primary coaxial antenna cable is then routed beneath the fender sheet metal and through a prefabricated and dedicated cable entry hole in the right cowl side panel into the interior of the vehicle. Inside the vehicle, the primary coaxial cable is connected to a secondary instrument panel antenna coaxial cable with an in-line connector that is located behind the right end of the instrument panel. The secondary coaxial cable is then routed behind the instrument panel to the back of the radio. Vehicles ordered with the radio delete option have a molded plastic plug installed in the antenna mounting hole on the right front fender, and a plastic plug installed in the cable entry hole of the right cowl side panel in place of the antenna body and cable.
The factory-installed radio antenna body and cable consists of the following components:
- Antenna adapter - The antenna adapter is sometimes also referred to as the antenna bezel or escutcheon.
- Antenna body - The die cast white metal antenna body is the mating structure between the antenna mast and the primary antenna coaxial cable.
- Antenna cable - This vehicle uses a two-piece antenna coaxial cable. The primary antenna cable is integral to the antenna body, and the secondary antenna cable connects the primary cable to the radio.
- Antenna cap nut - The antenna cap nut is a special, bright-plated threaded fastener that captures the antenna adapter and retains the antenna body to the fender sheet metal.
The components of the radio antenna body and cable cannot be adjusted or repaired. All factory-installed radios automatically compensate for radio antenna trim. Therefore, no antenna trimmer adjustment is required or possible after replacing the antenna body and cable or the radio. If an antenna body and cable component is damaged or faulty, it must be replaced. Other than the primary antenna cable, which is integral to the antenna body, the individual components of the antenna are available for service replacement.
The antenna body and cable connects the antenna mast to the radio. The radio antenna is an electromagnetic circuit component used to capture radio frequency signals that are broadcast by local commercial radio stations in both the Amplitude Modulating (AM) and Frequency Modulating (FM) frequency ranges. These electromagnetic radio frequency signals induce small electrical modulations into the antenna as they move past the mast. The antenna body transfers the weak electromagnetic radio waves induced into the rigid antenna mast into the center conductor of the flexible primary antenna coaxial cable. The braided outer shield of the antenna coaxial cable is grounded through both the antenna body and the radio chassis, effectively shielding the radio waves as they are conducted to the radio. The radio then tunes and amplifies the weak radio signals into stronger electrical signals in order to operate the audio system speakers.
The antenna body includes an integral flange that mates with and grounds the antenna body to the underside of the fender panel sheet metal. Above the fender panel, the antenna body has a short nipple that is externally threaded to accept the antenna cap nut. Inside the nipple is a plastic insulator tube, and inside this insulator is an internally threaded metal receptacle that accepts the adapter stud on the bottom of the antenna mast. The antenna adapter serves as an above fender interface to mount and secure the antenna body to the vehicle. The antenna adapter is a black molded plastic component that provides a functional transition between the top of the fender and the antenna cap nut, while concealing the edges of the antenna mounting hole and protecting the painted finish of the fender from marring as the antenna cap nut is tightened. The adapter is installed over and shrouds the threaded nipple of the antenna body, which is installed from under and protrudes through the top of the mounting hole in the fender. The antenna cap nut is installed on top of the antenna adapter and tightened onto the external threads of the antenna body nipple to effectively secure and ground the antenna body to the fender. Three notches on the outer circumference of the cap nut are engaged by matching projections of an antenna nut wrench (Special Tool C-4816) to facilitate the removal and installation of this special fastener. Proper tightening of the antenna cap nut is critical to ensuring proper grounding of the antenna body to the fender sheet metal, which is necessary for clear radio signal reception.
A short length of coaxial cable serves as the primary antenna cable. The center conductor of the cable is connected to the antenna mast receptacle. The outer wire mesh of the cable is connected to and grounded through the antenna body. One end of the primary antenna cable is securely crimped to the lower end of the antenna body, while the opposite end features a simple push/pull-type male coaxial cable connector that serves as the in-line connector to the instrument panel (secondary) antenna coaxial cable. The primary coaxial cable includes a grommet that seals the cable to an entry hole in the right cowl side outer panel where the cable passes into the passenger compartment of the vehicle. The secondary antenna cable has a push/pull-type male coaxial cable connector on the radio end, and a push/pull-type female coaxial cable connector on the opposite end, which serves as the in-line connector to the primary antenna cable. In the passenger compartment the primary cable is routed to the lower right side of the instrument panel, where it is connected to the secondary instrument panel antenna cable. The instrument panel antenna cable is routed near the instrument panel wire harness through the instrument panel to the radio and is secured to the instrument panel structural support with small metal push-on retainers. This two-piece antenna cable arrangement allows the instrument panel or the antenna body and cable to be removed or installed without disturbing the radio.
Fig.11 Antenna Mast:
ANTENNA MAST
A non-retractable, removable radio antenna mast is standard factory equipment on this model, unless the vehicle is ordered with an available radio delete option. The antenna mast is not installed on the vehicle when it is shipped from the factory, but is stored in the rear cargo area of the vehicle. Dealer personnel are to install the antenna mast into the antenna body as part of the preparation procedures that are performed just prior to new vehicle delivery. When installed, the antenna mast is the most visible component of the antenna unit. The antenna mast is a metal rod that extends upward from the top of the right front fender panel of the vehicle, near the right end of the cowl plenum. The antenna mast for this model is a fixed length, bright finished, stainless steel, rod-type unit. The lower end of the antenna mast has a threaded stud below a hex formation on a tapered adapter that is used to secure the mast to the antenna body.
The antenna mast cannot be adjusted or repaired. All factory-installed radios automatically compensate for radio antenna trim. Therefore, no antenna trimmer adjustment is required or possible after replacing the antenna mast or the radio. If an antenna mast is damaged or faulty, it must be replaced.
The radio antenna is an electromagnetic circuit component used to capture radio frequency signals that are broadcast by local commercial radio stations in both the Amplitude Modulating (AM) and Frequency Modulating (FM) frequency ranges. These electromagnetic radio frequency signals induce small electrical modulations into the antenna as they move past the mast. The antenna mast is connected to the center wire of the coaxial antenna cable through the antenna body. The coaxial antenna cable conducts these induced electromagnetic radio frequency signals from the antenna mast to the radio. In order to operate properly, the antenna mast must not be grounded to any part of the vehicle.
A tapered adapter with a hex formation on the fender end of the mast has a threaded stud that is installed into the threaded receptacle of the antenna body to secure the mast to the vehicle. The hex formation on the adapter at the fender end of the mast above the stud allows the mast to be easily removed or installed using a small open-end or adjustable wrench.