Town & Country V6-3.8L VIN L (2006)
Radio/Stereo Noise Filter: Description and Operation
Radio noise suppression devices are factory-installed 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.