The wlan doesn't work-it used to until last week! The flashing amber light on the front is completely gone and does not flash anymore! and it says that NO wireless networks detected - although my friend's laptop in the same house is still working from the same router

No, it means it cannot set up a Internet Connection.
Try Powering Off and On again, if not contact your Internet Supplier.

It probably needs to be re-programed
I have a viper model 5101 and this is how you program it Hope it helps !

Programming the Viper Remote Starter 5101

Unlock the doors before starting

Push and hold f button for 8-10 seconds until amber light is on solid

Push Remote start button for about 4 seconds till amber light flashes 3 times

Put key in IGN to the on position but don

1-If you never shut off the device try to turn off for 4 hours and try to use it again.
2-The bottom light must flash when is on,if not you have a power supply or net cable problem.
3-If the top light is amber is indicate you have a disk problem
4-Do a power cycle
5-if the problem continues run the disk diagnosis utility from the web interface
6-If fails the drive needs replacement, check for warranty
7-Try to do a system reset.Press and hold the switch( a small hole at the bottom of the Ethernet) until the top front light flash and allow the unit to restart.

If you need more help come back.Post / thumbs / testimonial are welcome!

when i turn the printer on the light flashes amber several times, then green then repeats flashing amber, and back to green etc. turning it off and back on made no difference. last time it worked normally after being off for a couple of days, but now it is doing that again.

Amber light flashes 7 times, then green for a couple of seconds, then amber 7 times etc.

i had same prob, tried unplugging three times
then unpluuged for 5mins
, plugged back in left it alone, ie didnt touch remote or front panel, until it settled down ~15mins, green light came on (doesn't normally)
and everthing seems ok now

I had the same issue with my Dell Dimension 5150 and I replaced the front I/O USB Audio Panel and it booted right up.

You first need to make sure your memory is secure.

You do 2 things. See the service manual
http://www.eserviceinfo.com/download.php?fileid=38984

FLASHING AMBER LIGHT FIX. This maybe in fact a motherboard issue, but actually its a bit more. You can and should replace the power supply with a more powerfull one as it will help overall, but the issue is Really the front USB ports and 2 issues concerning them, 1 some devices pluged into them have boot sequences of their own, (remember your boot seq goesfrom,USB,CD,ARRAY)etc.
So if the device isnt design with its own OS, the mis-boot will get stuck Hence the Flashing light. and 2. the front USB ports dont supply alot of power upon bootup. and the devices pluged into them will again cause a mis-boot. Simply unplug everything from the FRONT usb ports. You may have to shut the computer off and unplug the machine for about *15* minutes.
Enough to get the motherboard to downpower completely.
with the front usb ports clear, and the power cord unpluged, hold down the power button and plug in the machine. should boot no problem. So to sum things up. The motherboard is fine, it just not happy with so many usb ports (power wise). A larger power supply is a good idea but wont entirly fix the issue, Unplug front usb devices as they may have some form of bootup.

Power edge system are having two power input check the cables from the power outlet may be one is in contact otherwise one of your power supply gone means not working. Check the wires first then the power supply units