Porsche 996 TT, Repair Manual

Page: 1790 / 2099

Check the lead connections to the
injection nozzle. Check in particular for
loose or corroded connections.
2. Check resistance of the injection
nozzles. R = 12 Ohm +/− 0.6 Ohm.
Noise no longer present ’ End
Noise present ’ Check the points listed
above under Note once more.
Does the noise
not occur
when the car is
driving?
’ Step 3
2
3. Check for faults caused by
vehicle components which have
an influence on the speed.
4. Disconnect the component from
the power supply and test again.
Noise still present?
5. Check the wiring of the
components for unfavourable
positioning and loose or corroded
connections.
6. Lay the cables again or repair.
7. As an experiment, insert a functional
component and replace, if necessary.
’ End
Check the
radio reception
’ End
3
8. Check the wiring of the
components for unfavourable
positioning and loose or corroded
connections.
9. Lay the leads again or repair.
Noise still present?
As an experiment, insert a functional
component and replace, if necessary
’ End ’ End
Interference noise due to antenna
Note
Follow this test routine if the interference noises come from the antenna. •
As an experiment, it is worth making a comparison by inserting a rod antenna. •
Work instruction Yes No
1
1. Clean all connections.
2. Connect a ground strap to the
antenna plug.
3. Connect the other end of the ground
strap to a suitable point on the car
body.
4. Check the ground connection
5. Check all antenna mountings for good
ground connections with the negative
terminal of the battery.
6. Check all hardware mountings for firm
seating and clean ground connections.
Noise present ’ Step 2
Noise not present ’ End
’ End
einordnung
Interference noises due to engine 1727