Battery drain

[DomP182]

I'm still finding my battery drains if left for a few weeks. It's a new bosch S4, I've done a parasitic draw test which highlighted the interior light as the problem so I sorted that but still the problem persists even though a draw test now shows minimal milliamp draw.

Any ideas?

 

[Darren61]

I found this happened to me. A few weeks is too long a time to leave it standing and I couldn’t work out if it was my car or just a Clio thing in general.

Opted for a trickle charger/battery conditioner to plug it in when not in use and it’s been fine since.

Could be worth a look?

 

[DomP182]

I found this happened to me. A few weeks is too long a time to leave it standing and I couldn’t work out if it was my car or just a Clio thing in general.

Opted for a trickle charger/battery conditioner to plug it in when not in use and it’s been fine since.

Could be worth a look?

I could do but I'd love it to just work as it should, doesnt help that I'm not exactly clued up with electrics

 

[TheEvilGiraffe]

A few weeks ?!

The alarm will be working.. might not be using much but multiply that over a months worth.....

If it's dying in a week or less, I'd say it's worth investigating. 2/3/4 weeks ?!

Trickle charger as above.

I have a NoCo one.. does the job. Plenty to choose from - find one that suits your application.

 

[DomP182]

A few weeks ?!

The alarm will be working.. might not be using much but multiply that over a months worth.....

If it's dying in a week or less, I'd say it's worth investigating. 2/3/4 weeks ?!

Trickle charger as above.

I have a NoCo one.. does the job. Plenty to choose from - find one that suits your application.

What is the normal acceptable amp draw for a 1*2?

 

[Touring_Rob]

What are you measuring? in milliamps.

 

[DomP182]

What are you measuring? in milliamps.

Yeah milliamps, I'm a bit worried its screwed what was a battery just one a year ago

 

[Touring_Rob]

No, sorry I meant how many milliamps do you measure - 10, 100, 1000?

 

[JamesBryan]

My drain turned out to be the alternator backdrawing current, that was several hundred milliamp iirc.

 

[DomP182]

No, sorry I meant how many milliamps do you measure - 10, 100, 1000?

Oh crap sorry, I forget now but pretty sure it was sub 10mA but it must be killing my battery somehow. Would the alternator drawing back require testing in a different way?

 

[JamesBryan]

10mA is nothing really 🤔

My draw was over 300mA.

 

[DomP182]

10mA is nothing really 🤔

My draw was over 300mA.

I wonder what the hells going on then, admittedly I've not driven it much but have had the battery off on charge.

 

[JamesBryan]

I wonder what the hells going on then, admittedly I've not driven it much but have had the battery off on charge.

Who knows... You could try doing the test again and disconnect the feed to the alternator and see if it goes completely.

 

[DomP182]

Out of interest for the last week or so I've left it unlocked and it's starting where as it would normally be pretty flat by now. Could it be the alarm causing the drain once armed and how do I check that?

 

[JamesBryan]

Out of interest for the last week or so I've left it unlocked and it's starting where as it would normally be pretty flat by now. Could it be the alarm causing the drain once armed and how do I check that?

Possible yeah.

I really don't know how the alarm is wired in on these 🤔

 

[obcuz]

I've bought several of those Bosh S4's, when one car went to the body shop with brand new S4 on board, after some months, it returned and the battery was completely buggered, probably left in a discharged state for some or all of that time (I guess).
They are guaranteed 4 years, so take to local garage and ask for a load test on the battery to be sure it's not duff?

 

[DomP182]

I've bought several of those Bosh S4's, when one car went to the body shop with brand new S4 on board, after some months, it returned and the battery was completely buggered, probably left in a discharged state for some or all of that time (I guess).
They are guaranteed 4 years, so take to local garage and ask for a load test on the battery to be sure it's not duff?

I bought it from ECP so exchange shouldn't be too hard hopefully

 

[Touring_Rob]

Out of interest for the last week or so I've left it unlocked and it's starting where as it would normally be pretty flat by now. Could it be the alarm causing the drain once armed and how do I check that?

Yes absolutely. This happened on a colleges Porsche and was quite difficult to trace. In the end I hooked up a rasberry pi and datalogged the current consumption over night but it would be just as easy to hook a multimeter up and carefully close the bonnet over the probe wires.

A battery of your size should manage 3.5amps for 20 hours, so 200 hours at 350mA (3 days), at 10mA your looking at over 290 days (ignoring self discharge).

So your current draw is either substantially over 10mA or your battery is shagged.

Rob,

 

[obcuz]

I bought it from ECP so exchange shouldn't be too hard hopefully

I bought mine online from ECP and they exchanged it no problem, as long as you got your receipt, the guy didn't even check it, but wouldn't count on that, as said just get a load test done.

 

[DomP182]

Yes absolutely. This happened on a colleges Porsche and was quite difficult to trace. In the end I hooked up a rasberry pi and datalogged the current consumption over night but it would be just as easy to hook a multimeter up and carefully close the bonnet over the probe wires.

A battery of your size should manage 3.5amps for 20 hours, so 200 hours at 350mA (3 days), at 10mA your looking at over 290 days (ignoring self discharge).

So your current draw is either substantially over 10mA or your battery is shagged.

Rob,

So if I connect my meter up in series with the battery, shut the bonnet and lock is to test the draw with the alarm set I should get a true result. I'll post my findings if this is correct

 

[Touring_Rob]

So if I connect my meter up in series with the battery, shut the bonnet and lock is to test the draw with the alarm set I should get a true result. I'll post my findings if this is correct

Yes boss. Worth leaving it for 10-30mins and checking it across that time. The Porsche needing an interior sensor of some sort however the current draw didn't go up the moment the alarm was set.

 

[DomP182]

Yes boss. Worth leaving it for 10-30mins and checking it across that time. The Porsche needing an interior sensor of some sort however the current draw didn't go up the moment the alarm was set.

Cheers mate I'll give it a go

 

[Touring_Rob]

My BMW battery only lasts 2-3weeks without being driven and I just bought a small solar panel which I leave in there while not using the car and the issue never happened again.

 

[Touring_Rob]

Cheers mate I'll give it a go

No worries, let us know how you get on and be careful not to cut into the multimeter probe wires when closing the bonnet 👍

 

[DomP182]

Still not done this but I have found the photo on my phone if the result last time, it was 13 milliamps. Today after retrofitting cruise control and road testing it all I've found that manually turning the headlights on dips the revs significantly to the point that stationary main beam will cause a stall.

 

[JamesBryan]

Still not done this but I have found the photo on my phone if the result last time, it was 13 milliamps. Today after retrofitting cruise control and road testing it all I've found that manually turning the headlights on dips the revs significantly to the point that stationary main beam will cause a stall.

As I mentioned earlier in the thread, 13mA is f**k all really.

But it does sound like your alternator is dead if it's cutting out whilst turning lights on.... Maybe it's not been charging the battery after all, and that's why your battery keeps dying?

 

[DomP182]

As I mentioned earlier in the thread, 13mA is f**k all really.

But it does sound like your alternator is dead if it's cutting out whilst turning lights on.... Maybe it's not been charging the battery after all, and that's why your battery keeps dying?

I Agree, I think it must be. The only reason I'd ignored that idea was because with the engine running I get 14.something volts so thought it was fine. Any other tests i can do on it?

 

[JamesBryan]

I Agree, I think it must be. The only reason I'd ignored that idea was because with the engine running I get 14.something volts so thought it was fine. Any other tests i can do on it?

Could get it drop tested.

Not sure how/if you can do it with a multimeter...

 

[DomP182]

Could get it drop tested.

Not sure how/if you can do it with a multimeter...

Today seemed like a good day to stand out in the cold testing the parasitic drain, so I connected my multimeter inline with the battery before opening the passenger door, heres what I found.

The fuse on the mA setting has blown so used Amps and straight away I was getting 0.08Amps (80 milliamps? )

Opened the passenger door and this went up to in the region of 0.12A so I clamped the door interior light switch assuming when iyhe light faded down the Amps would follow drop back to 0.08A but they didnt?

At this point I began pulling fuses, all fine except this fuse which I think is related to the interior lights or alarm sensors? This brought it down to 0.011Amps.

 

[DomP182]

Correction, its interior lights and radio I think. Fuse 29

 

[JamesBryan]

That's the boot light and also the mirror adjustment too I believe.

 

[Touring_Rob]

120mA is still low, higher than you would like but still not a huge deal in the scheme of things.

to put this into perspective. If you had a 1Ah battery, it would be able to supply 120mA for 8.3 hours.... You likely have something like a 40Ah battery so with 120mA drain your at 300+ hours.

If your engine stalls when lights are on your alternator is either duff or more likely your battery. A good test is to (with ignition on and engine off) measure the volts at battery (after you've been for a drive), then turn every light on (inc high beam) and measure the volts at the battery again. Simple test, let us know what you find.

 

[DomP182]

120mA is still low, higher than you would like but still not a huge deal in the scheme of things.

to put this into perspective. If you had a 1Ah battery, it would be able to supply 120mA for 8.3 hours.... You likely have something like a 40Ah battery so with 120mA drain your at 300+ hours.

If your engine stalls when lights are on your alternator is either duff or more likely your battery. A good test is to (with ignition on and engine off) measure the volts at battery (after you've been for a drive), then turn every light on (inc high beam) and measure the volts at the battery again. Simple test, let us know what you find.

I've just fitted a brand new Renault alternator as the last one began smoking. I dont use it much so 120mA is enough to mean its flat when I come to.

Definitely something up with something running off that fuse

 

[JamesBryan]

I've just fitted a brand new Renault alternator as the last one began smoking. I dont use it much so 120mA is enough to mean its flat when I come to.

Definitely something up with something running off that fuse

Is it maybe a case of the power taking a while to shut down on that circuit? Modern cars can be like that.

Like on my 182 I noticed I can still open the windows if I press the switch just after I've turned the key off.

 

[Touring_Rob]

Your engine should 1000% not be stalling so easily with the high beam on. Same happened to my alternator couple of weeks ago (seems really common at the moment!) the smoke is it becoming a hard short across your battery which will have done it no good. Try the poor mans load test above and see how much the battery volts fall by.

 

[Touring_Rob]

Is it maybe a case of the power taking a while to shut down on that circuit? Modern cars can be like that.

Like on my 182 I noticed I can still open the windows if I press the switch just after I've turned the key off.

Yes could well be. Could also be the part of the keep alive cct. with the radio or alarm has failed (often an old capacitor etc). You could try unplugging the radio to see if it falls.

If it were mine I and I left it for weeks without driving I would just install an isolator switch by the battery.

 

[DomP182]

Theres no stalling problems, it runs fine when I drive it, its sorn at the moment though.

I have thought about an isolator but I just want it to work as it should, I'll try your idea tomorrow Rob.

 

[Touring_Rob]

Still not done this but I have found the photo on my phone if the result last time, it was 13 milliamps. Today after retrofitting cruise control and road testing it all I've found that manually turning the headlights on dips the revs significantly to the point that stationary main beam will cause a stall.

Was this before you changed the alternator Dom?

 

[DomP182]

Oh yes! That was a used alternator I fitted which promptly started to smoke so shelled out £182 to Renault Wolverhampton for a shiney one

 

[Touring_Rob]

Ahhhh ok that makes sense. Mine also had a good time smoking it's tits off before I also pressed the £182 eBay button.