SZ2 - Suzuki Swift Battery drained overnight? - Andrew Gray

Hi, i've got a 2011 Suzuki swift, overnight the battery had drained, nothing seems to be left on, this car normally has no problems at all, it done it once at an airport after been left for 2 weeks.

Would it be possible that the blower in the on position could draw power? this is the only thing I can think of?

Kind Regards

Andy

SZ2 - Suzuki Swift Battery drained overnight? - elekie&a/c doctor
Unlikely to be a blower fault as this is igniton controlled.If you have the original battery fitted,it may have come to the end of its life.Get the electrical system checked properly.
SZ2 - Suzuki Swift Battery drained overnight? - Railroad.

Assuming the battery and charging system are perfectly good it's time to go back to basics. If your battery is draining overnight it'll be because something is still switched on and drawing current. Without wishing to give anyone a lesson in ohms law the time it'll take for the battery to discharge will depend on the resistance of the component through which the current is being drawn, which will determine the amount of current drawn. Amps = Voltage ÷ Resistance.

Connect an ammeter in line with the negative battery terminal and negative battery post. Have your probes or clips ready so that the circuit is never broken. This can be a bit fiddley but by no means impossible. Once the battery terminal is off and the ammeter in place the amount of current drawn will be shown on the display. Make sure your test leads are long enough to enable you to close the bonnet and still see the ammeter. Then lock the car up and wait. After a few minutes the ammeter display should show only a few milliamps which will be things that need a permanent battery supply. If it's more then you have an unacceptable drain which will discharge the battery over a period of time.

The amount of time can be calculated using the battery's amp hour (A/h) figure. If for example your battery is rated at 50A/h it means that the battery can be discharged at a rate of 50 amps for one hour, or 1 amp for 50 hours, or multiples thereof. Bear in mind that this calculation would be a based on a bettery that was in perfect condition and has a state of charge of 100%, and then be completely discharged down to 0%. In reality you will be unable to start the engine long before the battery gets anywhere near this discharged.

If you do have a drain you'll need to remove one fuse at a time until the drain disappears. When it does you'll have to isolate components on that circuit until you find the problem. A long process, and often head scratching.

SZ2 - Suzuki Swift Battery drained overnight? - FP

"... it done it once at an airport after been left for 2 weeks."

So the battery was flat after two weeks, some time back? That was your first warning - it shouldn't have happened.

Now it won't start after being used the day before? Almost definitely a dead battery - that is the first thing to check.

SZ2 - Suzuki Swift Battery drained overnight? - bathtub tom

The OP doesn't state the age of the battery.

That would be useful!

SZ2 - Suzuki Swift Battery drained overnight? - madf

The OP doesn't state the age of the battery.

That would be useful!

i assum same age as car and stuffed.

SZ2 - Suzuki Swift Battery drained overnight? - RobertT
Our 2011 SZ2 Swift had to have its battery replaced after 4 years.

Edited by RobertT on 03/09/2017 at 15:50

SZ2 - Suzuki Swift Battery drained overnight? - FP

This is one of those threads where it would be really nice to know what the outcome was/is. I'd better not go on again about good manners etc., as my reputation for grumpiness will not be improved.

SZ2 - Suzuki Swift Battery drained overnight? - KenC

Many of these small petrol cars have a smaller than average battery eg 45 to 50 amp hr, but plenty of electric circuits to maintain including permanently on running lights, built in sat navs etc

Could it be that the short journeys that small petrol cars are ideal for are just to short to recharge the "used capacity" of these small batterys ( so they end up being slighty undercharged all the time during local use. ( hence they slowly degrade )

As the weather cools and autumn approaches batterys face a double whammy on their demands.

a) cooler atomsphere affects the chemical efficiency of the battery

b) more demand eg heated rear screen/heaters and headlight on earlier

Two possible soloutions are 1, when the battery is dead look at te possibility of fitting a higher capacity ( plus 10 more amph) 2. get a quick hook up battery conditioner with a low charge rate and hook it up once a week during the cold weather or when the car is under used eg less than 80 miles a week

SZ2 - Suzuki Swift Battery drained overnight? - Railroad.

An alternator is very good at keeping a fully charged battery fully charged, but it's not so good at getting a discharged battery back to fully charged. Lucas always used to recommend that car batteries are trickle charged at least once per month during the winter months to maintain their performance and longevity, or more if the car was only used infrequently.

SZ2 - Suzuki Swift Battery drained overnight? - Cyd

Quite correct Railroad. Relying on the alternator to 'revive' a discharged battery is asking for trouble. I've been banging on about this for years on all sorts of forums, but few are listening.

I even include that advice in my video here:

https://youtu.be/AT_XmlwMVz4

SZ2 - Suzuki Swift Battery drained overnight? - RobertT
I replaced the dead Swift battery with a higher capacity one which cost about £20 more I think. Whether it was worth it I don't know but it's been ok so far.
 

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