Radio/Stereo: Description and Operation

AUDIO SYSTEM
An audio system is standard factory-installed equipment on this model, unless the vehicle is ordered with an available radio delete option. The standard equipment audio system includes an AM/FM/cassette (RAS sales code) stereo receiver, and speakers in six locations. Several combinations of radio receivers and speaker systems are offered as optional equipment on this model. The audio system uses an ignition switched source of battery current so that the system will only operate when the ignition switch is in the ON or Accessory positions.

The audio system includes the following components:
- Antenna
- Power amplifier (with premium speaker system only)
- Radio noise suppression components
- Radio receiver
- Speakers

Following are general descriptions of the major components in the standard and optional factory-installed audio systems.

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.

RADIO RECEIVER
Available factory-installed radio receivers for this model include an AM/FM/cassette (RAS sales code), an AM/FM/cassette/5-band graphic equalizer with CD changer control feature (RBN sales code) or an AM/FM/CD/cassette/3-band graphic equalizer (RAZ sales code). All factory-installed receivers are stereo Electronically Tuned Radios (ETR) and include an electronic digital clock function.

These radio receivers can only be serviced by an authorized radio repair station. See the latest Warranty Policies and Procedures for a current listing of authorized radio repair stations.

IGNITION-OFF DRAW FUSE
All vehicles are equipped with an Ignition-Off Draw (IOD) fuse that is removed when the vehicle is shipped from the factory. This fuse feeds various accessories that require battery current when the ignition switch is in the OFF position, including the clock. The IOD fuse is removed to prevent battery discharge during vehicle storage.

When removing or installing the IOD fuse, it is important that the ignition switch be in the OFF position. Failure to place the ignition switch in the OFF position can cause the radio display to become scrambled when the IOD fuse is removed and replaced. Removing and replacing the IOD fuse again, with the ignition switch in the OFF position, will correct the scrambled display condition.

The IOD fuse should be checked if the radio or clock displays are inoperative. The IOD fuse is located in the relay and fuse block. Refer to the fuse layout label on the back of the instrument panel fuse access panel for IOD fuse identification and location.

The radio receiver operates on fused battery current that is available only when the ignition switch is in the ON or Accessory positions. The electronic digital clock function of the radio operates on fused battery current supplied through the IOD fuse, regardless of the ignition switch position.

For more information on the features, setting procedures, and control functions for each of the available factory-installed radio receivers, see the owner's manual in the vehicle glove box.

SPEAKER SYSTEM
Standard
The standard equipment speaker system includes speakers in six locations. One full-range 8.9 centimeter (3.5 inch) diameter speaker is located in each end of the instrument panel top cover, one full-range 15.2 by 22.9 centimeter (6.00 by 9.00 inch) speaker is located in each front door and one full-range 15.2 by 22.9 centimeter (6.00 by 9.00 inch) speaker is located on each rear side panel of the vehicle, typically mounted over the rear wheel housings.

Each of the six full-range speakers used in the standard speaker system is driven by the amplifier that is integral to the factory-installed radio receiver.

Premium
The optional premium speaker system features Infinity model speakers in six locations. Each of the standard speakers in the six speaker stereo system are replaced with six Infinity model speakers in the same six locations. The premium speaker system also includes an additional Infinity power amplifier. The total available power of the premium speaker system is about 120 watts.

The six Infinity speakers used in the premium speaker system are all driven by the radio receiver through an Infinity power amplifier.

POWER AMPLIFIER
Models equipped with the Infinity premium speaker package have a separate power amplifier unit. This power amplifier is rated at 120 watts output. The power amplifier unit is mounted to the inboard side of the right instrument panel end bracket, outboard of the glove box opening under the passenger side end of the instrument panel. The power amplifier unit can be accessed for service through the glove box opening by rolling the glove box down from the instrument panel.

The power amplifier unit should be checked if there is no sound output noted from the speakers. For diagnosis of the power amplifier, refer to Speaker. The power amplifier cannot be repaired or adjusted and, if faulty or damaged, the unit must be replaced.

The power amplifier receives fused battery current from a fuse in the fuseblock module at all times. The internal circuitry of the power amplifier switches the amplifier on based upon a fused 12 volt output signal that is received from the radio receiver whenever the radio is turned on. The power amplifier receives the sound signal inputs for four speaker channels from the radio receiver, then sends the amplified speaker outputs for each of those channels through separate circuits to the six individual speakers.

ANTENNA
All models use a fixed-length stainless steel rod-type antenna mast, installed on the right front fender of the vehicle. The antenna mast has a spiral groove cut down its length to reduce wind noise. The antenna mast is connected to the center wire of the coaxial antenna cable, and is not grounded to any part of the vehicle. To eliminate static, the antenna base must have a good ground. The coaxial antenna cable shield (the outer wire mesh of the cable) is grounded to the antenna base and the radio receiver chassis.

The antenna coaxial cable has an additional disconnect, located on the outboard side of the right instrument panel end bracket and concealed by the right instrument panel end cap. This additional disconnect allows the instrument panel assembly to be removed and installed without removing the radio receiver.

The factory-installed Electronically Tuned Radios (ETR) automatically compensate for radio antenna trim. Therefore, no antenna trimmer adjustment is required or possible when replacing the radio receiver or the antenna.

RADIO NOISE SUPPRESSION
Radio Frequency Interference (RFI) and Electro-Magnetic Interference (EMI) noise suppression is accomplished primarily through circuitry internal to the radio receivers. These internal suppression devices are only serviced as part of the radio receiver.

External suppression devices that are used on this vehicle to control RFI or EMI noise include the following:
- Radio antenna base ground
- Radio receiver chassis ground wire or strap
- Engine-to-body ground strap
- Resistor-type spark plugs
- Radio suppression-type secondary ignition wiring.