High pitched whine and flat battery
 

Yesterday there was a really high pitch whine/squealing from around the satnav unit. I dug around and found if I moved the cables the noise stopped. However this morning I went to start the car and the battery was flat.

Could this be caused by the satnav drive or the towbar wiring? Also all my lights on the dash were one (airbag,abs, etc) would this be caused by the flat battery?

I've managed to disconnect the towbar wiring...

However, I now seem to have a battery/charging problem. Managed to just start my car on my way home from work, but all the warning lights were on and it came up with battery not charging fault...then when I was on my way home it came up with "disbaled engine" and the car cut out on a country lane!

Managed to get a jump start and it was fine for the drive back home, no lights came one, not even the charging fault. I've measured across the battery while the car is running and its saying 13.5v and 12v when the car is off.

Could the relay in the towbar have caused this by draining the battery and it being too empty to charge, or am I looking at a battery/alternator fault with something else draining it!?

What do you mean by it came up with "disabled engine"?

Was this on the message centre (lcd screen in between speedo and rev)?

Are you sure your battery is good? From the amount of battery related posts popping up atm I think the cold weather is starting to kill off the ones that are on their last legs.

I was driving down the road to get back home and it came up on the LCD screen "disabled engine" and the car cut out.

I'm going to ask the mechanics at work tomorrow if I can borrow one of their known good batteries and put mine on charge and see if that cures it.

Is there any other way myself I can test the battery and alternator?

I don't know of any way excpet taking the battery to a garage and asking for a stress test.

Hmmm, disabled engine sounds like you might have an immobiliser problem -or possible a bonkers ECU. Are your plenums dry? If they are wet they can cause ECU problems (admittedly it isn't likely on a petrol but it's worth checking anyway).

Hopefully the mechanics at work will be able to test my battery.

I think that message might have come up because there was literally no power left in the battery. When I first started the car, all warning lights came on, but never went off. When I rev'd the car at a constant 2k rpm for about 5 minutes, the airbag light went off, but as soon as the revs dropped, it came back on.

I've checked the plenums and all is clear and dry. I can't see it being a ECU/immobiliser problem as when the car was jumped by leads (turned side lights on first) it started and everything went off as normal.

Sounds very strange. Perhaps if you have a look at my thread about my 1.8's cutting out (and now non start) problems you might find something useful! http://www.the75andztclub.co.uk/foru...d.php?t=160631

Had the battery tested and its holding its charge, so that's ok.

Does anyone know what the voltage should be for the alternator? Also could there be something else draining the battery causing it to go flat?

Alternator. Voltage while idle should be above 13.5v.