Just wondering what are the usual culprits?

I have some investigation with this fabia as the battery was dying tonight, now on charge. I think it might be to do with the radio potentially, so I need to follow that up. There's also some wiring heading up under the centre trim, and into the boot area to power an odd parcel shelf install amp setup. It's disconnected so don't think that could be draining it. All lights appear to turn off as they should, etc.

Last call of course is the alternator which might not be charging. Is there an easy way to test that? Maybe VCDS testing the output voltage when its running? Should be around 14 volts with a working alternator.

Does anyone know the standing, tickover, under load voltage readings I should be getting?

Should add this is on a 1.4 16v.

After a full charge overnight, the voltage readout on tickover is 14v, and there is no battery light on the dash to suggest the alternator isn't working. I think I'm going to look at tracing back this wiring installation as far as I can to remove it right back to source.

90% its something aftermarket like the radio/ install

14v sounds good in terms of the alternator is working.

To propperly test the battery ull need to remove it or disconnect the leads.

The first thing I'd check are the two control wires from the alternator.

The battery is known good?

I have a receipt for the battery from September 2010, so I hope its still OK.

You need to check the alternator when it's under load too, because they have a variable duty field current controlled by the ecu, try with the output of the alternator with the rear heated window on and headlights, fan blower etc. See what voltage you are getting at various loads

You need to check the alternator when it's under load too, because they have a variable duty field current controlled by the ecu, try with the output of the alternator with the rear heated window on and headlights, fan blower etc. See what voltage you are getting at various loads

Shall do, cheers.

As an aside, I got all of this out today, but its not the source of a drain as it was merely a bundle of wires under a back seat, and I traced the other end which was all left loose/bundled around the gearstick underneath the centre trim. At least it's tidied up a bit now.....

Do you have a multimeter with an ammeter setting? What I would do is disconnected the negative battery terminal and attach the ammeter between the battery terminal and the battery wire and see what current drain you are getting at rest, that way you can start pulling fuses till you find where the source of the battery drain is.

the instrument cluster and ecu have a permanent power, so does the radio and alarm, brake lights, ignition switch, central convience unit, starter motor etc etc.

I have this, but I admit I have not used it before since buying it from Lidl quite some time ago.

I also have no idea how to operate it..... [noob!]

Its this one- http://www.hobby-hour.com/electronics/dt830b-digital-multimeter.php

Yer that'll do, plug the black into com, Red into the adc, then use the 10a setting on the switch.... Connect the black wire to the car battery terminal, red wire to the battery cable...... Warning, any load over 10a will low the internal fuse on the meter so no crag king the engine!

OK - Think I sussed it. Set to 20v on DC, link up pins to terminals on battery.

Edit: Just seen reply. Thanks

Put the red lead into the top of the 3 sockets. Put the black lead into the socket labeled COM.

Disconnect the negative lead of the battery, connect the red lead to this. Then connect the black lead tp the negative battery terminal.

Then turn the yellow knob to point at the red 10A range.

The ammeter is now part of tge circuit and will show the current draw.

Dont put the red on the positive and the black on the negative of the battery otherwise you will short out the battery and blow the fuse on the ammeter

Hope thst helps :-)

Edit: damn tom beat me to it lol

Understood, thanks. making it red and black and having to reverse this for applying to this job doesn't make much sense though

OK - I did the above and the meter never registered anything - Always said -0.00 - Assume that's a good thing?

Voltage with engine off was reading 12.42 when set to the "20" DC setting.

Checked the boot light?

Also, is fuse 60 "in" or pulled? Could be an alarm type issue.

Fuse 60 has been put back in and is working - I activated alarm chirps to verify this.

I have not checked any lights. I did verify the puddle lights were turning out when the door was closed, as were a set of LED puddle lights a previous owner has installed at some point.

Jason sorry I just re read what i wrote, I'm being a no bend, it should be red lead to the negative terminal, black lead to the battery cable.. Hence why your meter is showing -0.00 because the polarity is reversed.

what I would do is pull one fuse at a time and replace each one as you go, it's normal for a car typically to have unto about 0.05A of parasitic draw on the battery from ecus and modules etc.. As a rough guide a 5w lamp will give you about 0.4A of load.

It's raining now though. :( haha!

Sod it, I went out with a gore-tex on anyway.

I was a little worried as the meter went up to -0.5 first but then quickly down to -0.25 before settling at -0.10. Not sure if -0.10 is a bad drain or not? A bit like a 1.5w bulb then

Yes that's too high, it certainly would drain down a battery overnight especially if it's getting a bit tired.

Sooo, next mission when its dry then, find out where my -0.10 is going then..... Likely culprits so I can start a list? I am thinking of the radio first.... however it does turn off with the ignition, so its correctly wired into the switched live.

Radio is a possibility yes, especially if it's an aftermarket type, what some people do is wire up the switched and permanent lives together so that it is always on, ie doesn't turn off when the ignition key is pulled.

to be honest there are loads of possible places to look.

edit: ah just read that, you must have edited your post, also it might have had an aerial amplifier fitted behind the head unit straight to the permananent live.

ah, aerial amp of course! That could be it! They are meant to be in switched live as well.

I think I'll remove the bottom drawer under the radio, and remove the unit and check the wiring anyway. I don't think there can be much else as there's no surplus items connected to the battery/surroundings in the engine bay, and the radio is the only aftermarket thing in the car.