Hi all,

I've just installed a new car stereo this afternoon (Pioneer AppRadio 4 - SPH-DA120) and now my car won't start. There is still power to the stereo and headlights but when I turn the ignition all I hear is a fast-paced clicking noise. I disconnected the stereo and the noise is the same. I presume this means the battery has been drained, although I'm not quite sure how because although I played with the stereo for a couple of hours, I doubt that would be enough on it's own to drain the battery and it very much appeared to be switching itself off when I turned off the ignition.

Any thoughts on what I've done wrong? (I'm a bit of a novice in car wiring so speak slowly please!)

Sounds like battery to me - when I was installing my new head unit the car was slow to turn over after I'd been messing with it, and eventually I had to put the battery on charge for an hour or so as it dropped too low while I still faffed about.

Couple of hours with engine off? To prevent battery drain ford put a 1hour limit on it so youve probably drained the battery remember its not just the stereo youre powering the ecu pcm various dials etc

Sounds as though I misjudged the limits of the battery then - one embarrassing call to the RAC coming up tomorrow morning!

Thinking about it, I was probably fiddling around with it for quite a bit longer than 2 hours actually, so I guess it makes sense - but I'm curious now - many of these large screen stereos come with DVD players which you're legally forbidden from using whilst the car is in motion, so what's the point if you can't actually watch a DVD on them without draining the battery? It amazes me how little you can get out of a battery that size - the battery on an iPad is about 2% of the size and can power screen for a whole day. I know the car battery is doing more than that, but still...

Can see your point, but look at it this way - your iPad battery doesn't also have to operate a starter motor connected to various big bits of metal which don't want to move without some persuasion, plus there'll be fuel/air mixtures to compress and so forth.

The starter motor is probably the biggest load you can put on your battery, and it needs to be in a good state of charge to do this. Plus at the same time you'll have the rest of the car powered up so there's a fair few background amps being drawn too. Think if you tried to do the same with your iPad it would overheat and go pop very quickly!

Ideally you'd be able to power up the head unit on it's own, the Ford systems let you do this (for an hour) but the after-market units don't seem to do similar possibly because they're only powered when the ignition is on.

Sounds like you drained the battery a bit too much while fiddling with your new stereo, it happens :P

Charge the battery for a couple of hours, or bump start it down the street and take it for a half hour run afterwards :)

So it was the battery - I got the RAC out this morning and they tested it and said the battery was on it's last legs anyway and I just finished it off. I had them replace it for me and so far it seems fine with the new one.

Thanks for all the replies - glad it wasn't something I'd wired incorrectly with the stereo!

just make sure they put the right type of battery in ive known the rac and aa to put the wrong type ie lead acid batteries in

just make sure they put the right type of battery in ive known the rac and aa to put the wrong type ie lead acid batteries in

Urgh. Thanks for the tip, but my understanding of the underside of a car bonnet is such that I wouldn't know if the engine was turned upside down - I wouldn't have a clue what kind of battery I'm supposed to have! The last two or three I've had have been from the RAC and have been fine - what would I need to look for to check this?

The name of the battery if it has one on it open bonnet right hand top corner is the battery pop the cover off and take a look as long as its not a lead acid battery youll be fine