I fitted a new headunit into my peugeot 306 today, i was driving turning the voulume up pretty loud, and the stereo switched off, so did the clock and teh mileage reader and teh petrol gage droipped below red. The cra still drives but theese elctrics do not work, can someone please tell me how to fix this problem.

you blew a fuse.

does that mean that the stereo, petrol gage, and mileage meter will all work if i replace it?

They should, check the ground on your head unit and make sure all the new splices/connections are not chaffing or loose.

Thats exactly what happened when the alternator on my car went bad. If its hard to start tomorrow take it to get a new alternator ASAP before you get stranded.

Here's my story:
Mid Summer time 100+ degree weather and I am driving home from school. My stereo turns off, followed by my AC, then my clock turns off, lastly my RMP gauge dropped down to zero <thats physically imposible when you are driving the car or the car is running its just the electronics to the gauge stopped. Later that night after I am freaking out that I broke my car it got harder and harder to start. My battery kept dying and when I would try to start the car when I turned the key there was like a million clicking sounds. I took it into the dealer and sure enough it was my alternator.

They won't work at all now? Or they just didn't work for the rest of that driving session. If they don't work at all, yes you probably blew a fuse. If they are still working once you turned the car off and started it again, I'd lean towards the alternator.

I've had quite a few Peugeot 306s. Check the battery connections are tight. I had similar problems on my GTi-6. You need to just tweak them a bit tighter or better still take em off, lightly sand the terminals and tighten up again.

i was fitting a new head unit to my sisters car last nite, it is a 206 but exactly the same thing happened? all the lights came on and all the guages stopped working!could it be the altenator or could the new head unit be shorting out the rest of the electrics?