Car Alarm And Flat Battery

[MR2vince]

Hello peeps.

Gone out to the car today after it being stood a week or so, and the Battery is flat as hell, the Battery meter doesnt even move lol.

Is this quite normal in cold weather, as its a 5 month old Battery??

Ive recently fitted aftermarket amps in the car, that have constant Live feed, but only become live when the head unit turns them on, head unit doesnt become live untill ignition is on. Could this be flattening the battery, even though the amps havent flattened the battery before the car came off the road.

Also after charging the battery and reconnecting it, for some reason the horn sounds like an alarm, and the door marker lights flash, the indicaters dont flash.

Is this an alarm on my car or something else? Far as im aware the car only has the stock imboliser, that you turn off with a little fob that you stick in the dash, (that pisses you off when your in a rush and you have to faff about trying to get the thing to turn off!!!).

Or this some other warning devise???

vin

[boundsw]

If the amps are wired up on the remote feed from the Hu i doubt that will be flatening the Battery !

Cold weater kills batteries, so could just be that, check the fluid levels on the bat. Also go to a garage, most can put a tester accross the terminals and tell you if the Battery is any good !

[Jinxed]

:( have you got a solid ground? and are your connections to your amps tight(erm well fitted etc)? you say amps.... how many if your running more than 2 and a lot of other stuff it might be drawing too much current to charge the Battery and possibly damaging the alternator?

maybe the Battery is a bit dicky alternatively. just cos its 5 months old purchase, mighta sat on a shelf somewhere for considerably longer than that before purchase

good luck tho mate finding the cause and eliminateing it. its too cold now for public transport

[MR2vince]

its too cold now for public transport

Lol my car has no heater or demister, When it went for an MOT a water leak was found on the piping, and it meant dropping the tank to get to it, so the stupid mechanic bypassed the piping.

He failed to tell us what he had done, i didnt notice untill it rained and i couldnt see a thing so put the demister on and it didnt work.

So i opened the engine bay and there was bright orange pipe dust everywhere, so i guessed that the pipes were cut, on closer inspection i could see where he had bypassed the piping.

So untill untill i fix it i cant use the car in the cold or rain :(

have you got a solid ground? and are your connections to your amps tight(erm well fitted etc)? you say amps.... how many  if your running more than 2 and a lot of other stuff it might be drawing too much current to charge the battery and possibly damaging the alternator?

maybe the battery is a bit dicky alternatively. just cos its 5 months old purchase, mighta sat on a shelf somewhere for considerably longer than that before purchase

As far as i know everything is perfect, all the fancy lighting is LED so its really small current draw, and i only have one 1600w amp onboard at the mo.

I have tested the Battery myself with a meter and its flat as f***.

Gonna charge it tomorrow and see if it goes flat again.

Im also thinking about getting an alternator upgrade..............anybody know what upgrade i should be buying?

Cheers so far

Vin

[acstreet]

hi

my Battery once did this and went flat after every week it wernt used i used to always have to charge the Battery...............

so anyway my handbrake needed ajusted so i took it down the road to the garage and they done the handbrake.

the next mornin they could give me the car it wouldnt start because there was no power so they got and electrician and he said the alternator had died.

so i got a second hand alternator which didnt fit (how annoying) after the search of finding one that would fit i gave up and got a new alternator and the garage fitted it on for me

and then charged the Battery and now have no problem ,,,, battery hasnt gone flat since ..

so that might be your problem to i thought i would say as it sounds very similar.

cheers acstreet

[TurboTony]

There's several reasons why a Battery will go flat when left:

1. It's not charging in the first place - the best way to check is to start the car, remove any jump leads. Then connect a meter to the Battery and rev to around 3k. You should get a reading around 13v, any lower and it ain't charging.

2. You've got a current drain from somewhere - to check this you need to remove either the + or - terminal and connect an ammeter in line (most multimeters do this, but you need to put the + probe in another socket). With the ignition off you will see a small drain from stuff like alarms and interior light. Anything near to 1A shouldn't be there.

3. The Battery is knackered - Difficult to prove without the test equipment (I've got one, but I'm nowhere near you). If it ain't the above 2, than probably best to get a new one.

[Jinxed]

and theres always the cheapskate fault detection service.... call the aa or rac out if your a member and get them to diagnose it... hell i even pushed one of my old cars off the drive and down the road a little bit to make my callout legit as i didnt have homestart heh gl tho :) let us know what happens

[MR2vince]

HMM put the Battery back on today, and everything is fine......BUT

even with the ignition off and there is now power being being fed you can hear slight hissing from the Speakers. Does this meen that my amp is still on, even though its not lit up and all ignition is off?? therefore draining the Battery over the week??

this is odd

I may fit a Battery kill switch to cut all live to the amp.

the alternator is working fine

vin

[TurboTony]

Yep, sounds like the amps still on & will explain the flat Battery.

Where have you wired the amp trigger into? There should be an output on the head unit for it.

If you've got a meter, check for power between the remote and ground connections, with the stereo off there should bo nothing there (power on the +12v terminal is ok).

[Jinxed]

if the auto antenna is wired up properly it should only power the amp up when the stereo is turned on init. with that wired properly it should be ok ... or is there summat about mr2's with the power antenna and what iv'e heard is a strange 2 power wires that makes this not quite as straight forward?

[MR2vince]

There is no longer stock wiring in my car its all been replaced, the amp is connected to the head units remote output, and it works fine, when you turn the head unit off the amp goes off with it, and all the power status LEDs go out telling me the amp is off.

But even still i can hear hissing from the Speakers when everything is off.

[Jinxed]

are you grounding the Speakers to the Battery ? i know there are Speakers that need that but .... there really shouldnt be any sound output from the Speakers with it all turned off... seems like theres power going to them or summat... checked your wires for any core sticking out and making a contact with speaker connections? bit of a mad prob mate... first thing id be looking at is all of the ground wires, the entire ground circuit. can you put up a wiring diagram of how youve got it wired? stereos are a pain when a prob shows up... esp if they all neatly wired in and the trims all back :( ....are you sure youve got all the wires going from and to the right places between the head, speakers and amp? done a few now and i still manage to wire up the odd terminal to the wrong place cos im in a rush or thinking about what im doing next if you find what it is ...let us know