Sephia Sedan L4-1.6L SOHC 16V (1993)
Cellular Phone: Technical Service Bulletins
Audio - Noise From Speakers When Using Cell Phone
VOLUME
3
GROUP
Accessories
NUMBER
1004
MODEL
All
DATE
October 2004
SUBJECT:
AUDIO INTERFERENCE WHEN USING CELLULAR PHONE
This bulletin provides information relating to an intermittent, faint clicking sound from the audio speakers in some vehicles. The noise may be described
as either a clicking, popping or static sound from the dash area. This sound may be caused by radio frequency (RF) signals emitted by the occupants
wireless cellular phone.
Wireless telephones are hand-held phones with built-in antennas, often called cellular or cell, mobile or PCS phones. Wireless telephones are two-way
radios. When a person speaks into a wireless telephone, it picks up the persons voice and converts the sound to radio frequency energy (or radio waves).
The radio waves travel through the air until they reach a receiver at a nearby base station or cell tower. The base station then sends the call through the
telephone network until it reaches the person you are calling.
When a person receives a call on his/her wireless telephone, the message travels through the telephone network until it reaches a base station close to
his/her wireless phone. Then the base station sends out radio waves that are detected by a receiver in his/her telephone, where the signals are changed
back into the sound of a voice.
