Okay guys.

My car won't start after a few days of fully charging a the battery from a wall socket (using a car battery charger).

I initially thought it was the alternator not charging the battery well enough. I installed a new alternator and a new alternator belt. I also have installed a new battery.

The car is still draining the charge after a few days/nights, making it impossible to start the engine.

I have no after-market stereo or alarm installed. I have cleaned all the earthing points too.

Just guessing here but I'm thinking it could be a relay or something being stuck open and therefore slowly draining the battery charge.

How on earth do I diagnose and fix this problem?

Any suggestions? It's driving me mad. Especially after shelling out for a new alternator. Not a particularly cheap part.

Thanks.

Petrol or diesel

quaffle said:

Okay guys.

My car won't start after a few days of fully charging a the battery from a wall socket (using a car battery charger).

I initially thought it was the alternator not charging the battery well enough. I installed a new alternator and a new alternator belt. I also have installed a new battery.

The car is still draining the charge after a few days/nights, making it impossible to start the engine.



I have no after-market stereo or alarm installed. I have cleaned all the earthing points too.

Just guessing here but I'm thinking it could be a relay or something being stuck open and therefore slowly draining the battery charge.

How on earth do I diagnose and fix this problem?

Any suggestions? It's driving me mad. Especially after shelling out for a new alternator. Not a particularly cheap part.

Thanks.

Click to expand...

It could still be an alternator problem. The Alternator needs a 12 volt connection coming from the dash indicator light. So firstly you need to confirm you have at least 14V when idling. Once you have confirmed that side is Ok then disconnect the negative from the battery and put a 5W bulb between the negative cable and the battery. Then all you have to do is disconnect stuff step by step till the bulb goes out.

jazz452 said:

Petrol or diesel

Click to expand...

It's a 1.2 L 16v Active Sport model, so petrol.

judderbar said:

It could still be an alternator problem. The Alternator needs a 12 volt connection coming from the dash indicator light. So firstly you need to confirm you have at least 14V when idling. Once you have confirmed that side is Ok then disconnect the negative from the battery and put a 5W bulb between the negative cable and the battery. Then all you have to do is disconnect stuff step by step till the bulb goes out.

Click to expand...

I have 14v when idling using my multimeter on the voltmeter setting.

Disconnect stuff? How do you mean?

Can anyone shed some more light on this. This one is really perplexing me.

Hi mate,

Follow THIS guide I made on Parasitic drain testing!.

You will always have some drain on a modern vehicle as certain parts never FULLY "go to sleep"

Alan

I was going to refer you to a youtube video on parasitic draw but the above guide does it all. Best one I've seen, simple and clear. Do what it suggests and keep pulling fuses until you find what is causing the draw, Aftermarket alarms are a good source of problems as well. Just in case anybody is not totally familiar with multi meters there are plenty of videos on youtube showing how to use them. They are one of the most essential "tools" to have in the box. Just a basic knowledge of using them is usually enough to get you out of bother.

a1ant said:

Hi mate,

Follow THIS guide I made on Parasitic drain testing!.

You will always have some drain on a modern vehicle as certain parts never FULLY "go to sleep"

Alan

Click to expand...

Perfect. Thank you, Alan. Guess I'll give this a go.

digger58 said:

I was going to refer you to a youtube video on parasitic draw but the above guide does it all. Best one I've seen, simple and clear. Do what it suggests and keep pulling fuses until you find what is causing the draw, Aftermarket alarms are a good source of problems as well.

Click to expand...

Yes, I have heard of after market head unit and alarms causing issues. I don't have anything after market installed though. I think it might be a broken wire or something unfortunately.

a1ant said:

Hi mate,

Follow THIS guide I made on Parasitic drain testing!.

You will always have some drain on a modern vehicle as certain parts never FULLY "go to sleep"

Alan

Click to expand...

Following your guide I have confirmed my alternator is working correctly. It is a brand new, genuine part so I expected that.

However, when I come to check for "parasitic drain", I actually get a reading of 0.00 Amps (when set to 10A) and no reading when I set to microamperes (mA). So I'm no closer to solving the issue here

There should be some draw. When dis- or reconnecting the battery you always get a little spark. The size of it is a good indicator of the draw. You have disconnected the positive lead from the battery and are putting the meter in to the gap ? ( had to ask ). Switch something on like the interior light or radio and try again.

I cannot comment on why you see no drain using a multimeter when going through the parasitic battery drain testing proceedure. But I have a few comments I hope will help. Firstly the alternator on modern cars will not reserect a heavilly discharged battery, no matter how long a drive you take to 'recharge the battery', but it is an often quoted tip that older drivers (like me give, who hail from an era when you could actually recharge a battery in this way) only a charging period on a battery charger will do this and it is advisable to use a low amp charge cycle so the battery is not damaged internally by overheating causing plates to warp and internal shorts to occur. If the battery is the correct capacity for the car and is new, so capable of holding a full charge, then even if the car is left unused for a couple of weeks or more it should certainly be able to start the car.
If the battery is loosing capacity so badly in such a short time that it will not start the engine then there is either a 'parasitic drain' or the battery is faulty. Some sources of drain are typically an interior curtesy light remaining on - some sunvisors have mirrors with such lights. When the visor is folded up the light is hidden even when on but are quite enough to flatten the battery. Volvo's sometimes have this problem and yet they have huge batteries - the one on mine is bigger than what we used to have on our farm tractor!
My daughter's Punto (8v) last year had this problem and the solution was a new quality battery. Having done everything you have outlined already, have you got recourse to contact the new battery supplier and say you suspect it is defective? You have a very good case for doing so in my opinion and until you can be sure your battery is fine, everything else is a frustrating waste of time!

Thank you all for your helpful replies and suggestions.

I have managed to find which circuit is the culprit by disconnecting fuses one at a time.

It is F39. As far as I can tell it is the fuse for the interior light (that illuminates when the door is open) and the radio/CD player.

How do I go about solving this issue though? I actually do quite like driving to music.

The head unit is the standard, factory fitted model. However, this odd wire hanging loose near the fuse box suggests the previous owner might have installed a custom unit? Any chance this could be related to the problem?





Suggestions of where to go next would be very welcome.

quaffle said:

Thank you all for your helpful replies and suggestions.

I have managed to find which circuit is the culprit by disconnecting fuses one at a time.

It is F39. As far as I can tell it is the fuse for the interior light (that illuminates when the door is open) and the radio/CD player.

How do I go about solving this issue though? I actually do quite like driving to music.

The head unit is the standard, factory fitted model. However, this odd wire hanging loose near the fuse box suggests the previous owner might have installed a custom unit? Any chance this could be related to the problem?

Suggestions of where to go next would be very welcome.

Click to expand...

Is the boot light switch stuck?

As soon as I saw the thread title, I was going to ask if you had an aftermarket stereo? Have you followed the guides to wire it in correctly if so, otherwise they do like to stay on and keep draining the battery.

judderbar said:

Is the boot light switch stuck?

Click to expand...

I don't actually have a light in the boot. Did some models not have them? Where is the boot light switch just in case? Is there any reason the previous owner might have removed the boot light if all models came with one?

Eklipze3k said:

As soon as I saw the thread title, I was going to ask if you had an aftermarket stereo? Have you followed the guides to wire it in correctly if so, otherwise they do like to stay on and keep draining the battery.

Click to expand...

I don't have an aftermarket stereo installed. It is the standard Blaupunkt unit that comes from factory:



However, a user wrote on my Visitor Messages here on the forums:

s and b said:

hi
looked in and saw your post
a lot of fiat radios cause a drain when they get old
easiest way to check is a 501 bulb the type in your number plate light
put it in series between battery and earth clamp
get a friend to turn ignition on then off
you will see light pulse then after a minute it should go off as body computer goes to sleep
if it continues to light then radio needs junking

Click to expand...

Is that true about the standard Fiat radios? Because if it is, that is certainly the problem I'd wager.

Right. After a lot of trial and error I have located this issue to the circuit with the fuse F39. This circuit has the interior light, stereo, diagnostic port and the boot light (not installed) on it. When I pull the fuse (F39) the battery does not drain over night.

The battery still drains with the fuse in and the stereo disconnected so I know it's not the head unit that is causing the issue.


The problem is, everything seems to be operating fine on this circuit. The interior light isn't staying on, the head unit isn't even installed at the moment and neither is the boot light. The diagnostic port seems to be working just fine too.

I have suspicions that someone may have installed an aftermarket alarm system on this circuit as it would need a constant feed like the one supplied to the stereo. When looking in the footwell I have seen a multiple wires that look like they've been added in so I'm guessing this is the case.

I can't find a wiring diagram that has the interior light or diagnostics port on it though. I have one for the audio system but the wiring seems original.


What would someone wire an aftermarket alarm too? Am I right in thinking it might be this circuit?

I'd really like some help or input on this guys but so far this problem look unfix-able to me

quaffle said:

Right. After a lot of trial and error I have located this issue to the circuit with the fuse F39. This circuit has the interior light, stereo, diagnostic port and the boot light (not installed) on it. When I pull the fuse (F39) the battery does not drain over night.

The battery still drains with the fuse in and the stereo disconnected so I know it's not the head unit that is causing the issue.


The problem is, everything seems to be operating fine on this circuit. The interior light isn't staying on, the head unit isn't even installed at the moment and neither is the boot light. The diagnostic port seems to be working just fine too.

I have suspicions that someone may have installed an aftermarket alarm system on this circuit as it would need a constant feed like the one supplied to the stereo. When looking in the footwell I have seen a multiple wires that look like they've been added in so I'm guessing this is the case.

I can't find a wiring diagram that has the interior light or diagnostics port on it though. I have one for the audio system but the wiring seems original.


What would someone wire an aftermarket alarm too? Am I right in thinking it might be this circuit?

I'd really like some help or input on this guys but so far this problem look unfix-able to me

Click to expand...

Take the stereo physically out for a few days
And reinstall the fuse

Does the battery go flat then?

Its not uncommon for the original HU's to have issues
the micro switch to tell it a CD has been inserted, often plays up, resulting in the car turning the stereo on and off all the time

Its easy to remove - 2x pin sets and yank out - disocnnect and listen to the little engine work for a few days

Also - take your battery to Halfords, they do a free capacity test

If the battery is weak to start with - a small drain is made to look 10X worse

Ziggy

Ziggy122 said:

Take the stereo physically out for a few days
And reinstall the fuse

Does the battery go flat then?

Its not uncommon for the original HU's to have issues
the micro switch to tell it a CD has been inserted, often plays up, resulting in the car turning the stereo on and off all the time

Its easy to remove - 2x pin sets and yank out - disocnnect and listen to the little engine work for a few days

Also - take your battery to Halfords, they do a free capacity test

If the battery is weak to start with - a small drain is made to look 10X worse

Ziggy

Click to expand...

I've taken the headunit out and reconnected the fuse and I still get a battery drain. I'm quite sure it's not the head unit.

I have tried with 2 different battery. One being a new one and the other being an old spare I have lying around that I know to be in working order.

quaffle said:

I've taken the headunit out and reconnected the fuse and I still get a battery drain. I'm quite sure it's not the head unit.

I have tried with 2 different battery. One being a new one and the other being an old spare I have lying around that I know to be in working order.

Click to expand...

Its a shame your multi-meter didnt give an actual reading of whats been drawn....

Next i'd be taking interior light out and leaving it disconnected
followed by what ever else is attached to it....

Ziggy

Ziggy122 said:

Its a shame your multi-meter didnt give an actual reading of whats been drawn....

Next i'd be taking interior light out and leaving it disconnected
followed by what ever else is attached to it....

Ziggy

Click to expand...

Right. Disconnected the interior cabin courtesy light now and re-installed the [F39] fuse. Let's see how this goes... I will report back.

quaffle said:

Right. Disconnected the interior cabin courtesy light now and re-installed the [F39] fuse. Let's see how this goes... I will report back.

Click to expand...

Daft question - it aintt an LED bulb in it?
LED bulbs often glow dim even when off - due to residual current - so it may be "switched off" but since it needs like 4v to start to glow - it'll take current and drain the battery

Failing that - i'd take the cluster off next

Ziggy