Interference Noises - Porsche 996 TT Repair Manual

amplifier.
8. Disconnect the lead on the
amplifier side.
9. Insert an interference
filter.
10. The negative terminal of
the interference filter
should be installed facing
towards the amplifier.
Interference noises remedied?
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Interference noises

Note
• This procedure is designed to help you find out how the interference noise has entered the system.
• In the following subchapters, the various interference noises are differentiated.
• The battery must be fully charged.
• No charging unit may be connected.
Work instruction
1 Does the interference noise
complained about by the
customer really exist?
2 Can the interference noise be
heard in all the loudspeakers?
3 Disconnect the antenna from
the radio and observe the
interference noise.
Does the interference noise
change or disappear?
4 Does the interference noise
change?
Interference noises
einordnung
Yes
Disconnect all electrical connections to
retrofitted accessories, such as two−way radios,
mobile telephones, radar detectors, etc.
' Step 2
Slowly pull the receiver component(s) out of
the holder and observe the noise. Does the
interference noise change or disappear in the
process?
Yes ' Step 4
No ' Step 3
=> Interference noise due to antenna
=> Interference noises due to alternator
=> Interference noises due to engine
=> Interference noises due to power supply
No
' End
=> Interference
noises, checking
cable
connections
=> Interference
noises due to all
looudspeakers
=> Interference
noises due to all
looudspeakers
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