Porsche 996 TT, Repair Manual

Page: 1784 / 2099

91 20 02 Checking complaints about car radio system
Malfunctions in radio system
Reduced sound quality in one or more loudspeakers
Remedying problems with the amplifier
Interference noises
Electromagnetic compatibility (EMC) − Troubleshooting
Tools
top of page
Malfunctions in radio system
1. Check error and customer complaint.
2. Switch ignition off and remove ignition key.
3. Remove radio fuses (ignition and memory).
4. Wait approx. 3 minutes until all components are free of tension.
5. Insert fuses again.
6. Check error and customer complaint
again.
Work instruction Yes No
1 Check error and customer complaint
again.
Radio function OK? Check battery charging condition and
battery cables for perfect contacts.
If the problem persists, contact radio
manufacturer
’ End Does radio have a
CD player or a
magnetic−tape
drive?
Yes ’ Check
signal lead
No ’ Go to Step 2
2 Does radio have a display? If an audio signal can be heard, connect
a functional radio
’ Step 3
If no audio signal can be heard ’ Step 5 ’ Step 6
3 Does the system now function
perfectly? Replace radio
’ End => Interference
noises
’ End
4
7. Check all radio connections.
8. Check voltage at the connections
battery and ignition .
9. Check ground connection of
radio.
Radio function OK?
Repair wiring harness or plug
connection
’ End Connect
functional radio
’ Step 3
5
10. Disconnect audio connections
from radio.
11. At maximum volume setting,
measure the alternating voltage at
13. Check connection between the
radio and the amplifier with a
multimeter.
14.
Connect
functional radio
’ Step 3
91 20 02 Checking complaints about car radio system 1721