Town & Country V6-3.3L VIN R (2003)
Radio/Stereo Noise Filter: Description and Operation
RADIO NOISE SUPPRESSION COMPONENTS
Radio noise suppression devices are factory in stalled standard equipment on this vehicle Radio Frequency Interference (RFI) and
ElectroMagnetic Interference (EMI) can be produced by any on-board or external source of electromagnetic energy These electromagnetic energy
sources can radiate electromagnetic signals through the air, or conduct them through the vehicle electrical system.
When the audio system converts RFI or EMI to an audible acoustic wave form, it is referred to as radio noise. This undesirable radio noise is
generally manifested in the form of "buzzing," "hissing, popping, "clicking," "crackling," and/or "whirring" sounds. In most cases, RFI and EMI
radio noise can be suppressed using a combination of vehicle and component grounding, filtering and shielding techniques. This vehicle is
equipped with factory-installed radio noise suppression devices that were designed to minimize exposure to typical sources of RFI and EMI;
thereby minimizing radio noise complaints.
Factory-installed radio noise suppression is accomplished primarily through circuitry or devices that are integral to the factory-installed radios,
audio power amplifiers and other on-board electrical components such as generators, wiper motors, blower motors, and fuel pumps that have been
found to be potential sources of RFI or EMI.
There are two common strategies that can be used to suppress Radio Frequency Interference (RFI) and ElectroMagnetic Interference (EMI) radio
noise. The first suppression strategy involves preventing the production of RFI and EMI electromagnetic signals at their sources. The second
suppression strategy involves preventing the reception of RFI and EMI electromagnetic signals by the audio system components.
The use of braided ground straps in key locations is part of the RFI and EMI prevention strategy These ground straps ensure adequate ground
paths, particularly for high current components such as many of those found in the starting, charging, ignition, engine control and transmission
control systems. An insufficient ground path for any of these high current components may result in radio noise caused by induced voltages created
as the high current seeks alternative ground paths through components or circuits intended for use by or in close proximity to the audio system
components or circuits.
Preventing the reception of RFI and EMI is accomplished by ensuring that the audio system components are correctly installed in the vehicle.
Loose, corroded or improperly soldered wire harness connections, improperly routed wiring and inadequate audio system component grounding
can all contribute to the reception of RFI and EMI. A properly grounded antenna body and radio chassis, as well as a shielded antenna coaxial
cable with clean and tight connections will each help reduce the potential for reception of RFI and EMI.
