Kia Picanto parasitic battery draw

ps the 0.3A occurs only after I first put the multimeter probes on the battery negative post and cable clamp, so it's when the car first gets battery power.

That is all quite normal - the cars systems boot up, ready for you to start the car, and drive off. If you don't do that, then the system fall back into low power sleep mode, until next woken up. What may be the issue, is the car constantly being brought out of sleep mode, thus flattening the battery.
 
I've finally fitted a kill switch. It was a bit difficult because the negative battery terminal lead from the car is only just long enough to reach the negative post of the battery, and couldn't reach the negative post of the kill switch, until I put the whole lot down the back of the battery.
Also, as the Picanto uses a T3 (Japanese) style battery, with much smaller posts than T1 (all other types of battery), I had to cut the negative post off one of the three flat batteries I've accumulated since the parasitic drain started, and then replace the post that comes with the kill switch, with the cut off post.

I had to put the cut off post in a clamp, then drill a 4.5mm hole in it (it's lead, so easy to drill), and then screw the bolt that came with the kill switch into it. I started the thread with about two turns, then took the screw out, then put the bolt through the copper rod that sticks out of the kill switch, and then into the post - because once I'd got the bolt all the way in, I didn't want to have to take it out, as it would have been cutting its own thread. Luckily it worked first time, and is rock solid - although it looks a bit Heath Robinson.
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I bought two brass T3 to T1 battery post adaptors, and obviously only used the one for the negative post (I didn't realise that battery posts on a battery are two different sizes, positive and negative, to help prevent accidentally putting the wrong clamp on. Chance would be a fine thing with my Picanto, there isn't a millimetre of give in the negative battery cable from the car.)

I put the shim on, and initially put too much Vaseline on, which meant that as I tightened up the clamp from the kill switch, it rose up the battery post and eventually was loose. I cleaned off the Vaseline and put the clamp back on, and tapped it down further onto the post with a spanner, before tightening it up. This time it was rock solid.

After I attached the car negative clamp to the cut off post that I had bolted to the kill switch, I had to put the kill switch itself down behind the battery, because there was no spare negative lead to pull it up on top of the battery - which is where it is supposed to be. It comes with a double sided sticky pad, so you can stick it to the top of the battery.

Anyway, I then put the bubble wrap back which the kill switch came in, completely around the kill switch and the terminals, just to keep them from touching anything - if both terminals on the kill switch touched some metal, it would make the circuit and then my battery would probably drain again, because of the parasitic load.

The kill switch works perfectly with the remote control, it shows 12.4V on its LED display, with the engine off, and 14.4V (I think) with the engine on. It came with two remote controls, and they are really high quality, they have a nice feel to them, and look really well made, and work perfectly. I took the batteries out of the spare remote control, while I keep it in my house, and noticed that it has two CR2016 batteries, on top of each other, so presumably it needs 6V, not 3V.
After using the non-spare remote control to turn off the battery connection, I checked the car keyfob no longer opened the doors, and it didn't. I also checked the kill switch several times by putting the car headlights on, and turned them on and off with the kill switch. The car started fine, so the kill switch can obviously cope with the current needed to do that.

So at the moment, while I haven't fixed the parasitic drain problem, I no longer have to worry about it.
 
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Be very careful with those 12v cables, make sure the lugs are well insulated, and cannot possibly make contact with any bodywork. The concern is not the volts, but the current available if the battery is shorted - it can make a terrific mess, and the hot metal flying around, can cause a fire.
 
I will get something much thicker to put around the kill switch and the contacts, maybe the toe end of an old shoe, and duct tape it around, so it can't possibly make contact with the car body.
 
Only just read this, I did note:- during lock down, my wife's Jaguar XE would restart charging at the same time every day, around 11 am, seem to remember. The charger would charge the battery to 14.4 volts, then switch off until the battery reached 12.8 volts, so one would expect it to kick in every so often, but not the same time every day. I assume it sends info back to Jaguar at this time.

Ammeters for cars are traditionally
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which are not that accurate, and hard to read under an amp, to put a hard-wired ammeter in the circuit means disconnecting the battery, and this will likely restart some things when reconnected, the hall effect clamp-on
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may well-read AC amps down to 1 mA, however the DC scale requires zeroing, and I have found hard to get an accurate reading under 10 mA, and to data load that reading, you are talking about some really expensive equipment.

So the easiest way, is data log a battery charger, I am doing this now with my own Kia 1740667560915.pngonce the battery is fully charged, the battery charger will drop to zero, Battery chargers.jpg the old Lidi to the top, (3.8 amp) was rather good for this, but it would only return to a 0.8 amp charge, the new one bottom, will return to a higher rate of charge, and also starts off at a higher rate, and is what I am using now.

This method also has the advantage you end up with a full charged battery. The smallest dash lamp bulb use to be 2.2 watt, and a boot light 10 watt, but since the LED this is much reduced, but a boot light at 10 watt, with a 90 amp/hour battery, it would take nearly a week to fully discharge, but the problem is, a fully discharged battery also takes a long time to charge. So it builds up over time.

I have noted that a battery left for some time part discharged, can take a week or more to fully recharge on a battery charger which is running 24/7, so on a car only used 2 hours a week, it will likely never fully recover, does not matter if the alternator can put out 50 amps, the battery can only accept the charge at more like an amp, if even that much.

I note wife's Jaguar XE will stop activating the stop/start, and after 5 days charge it will return to activating the stop/charge, and I use that to warn me when it needs the battery charging from the mains. I have found the charger showing fully charged is often not correct, the energy meter showing it is cycling on/off with a large space in the mark/space ratio as time goes on, so try to use the charger for at least 24 hours each time used.

It took around 20 hours to recharge, it was on for 5 hours the day before, this Kia battery charge, second day..jpg was second time put on charge, it takes so long, we often simply don't give them enough time to recharge.
 
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I will get something much thicker to put around the kill switch and the contacts, maybe the toe end of an old shoe, and duct tape it around, so it can't possibly make contact with the car body.

If an MOT inspector sees that, then it will be an immediate fail, for exactly the same reason a inadequately fixed battery is a fail. The risk is of it shorting and setting fire to the vehcle, with the slightest of accidents.
 
If an MOT inspector sees that, then it will be an immediate fail, for exactly the same reason a inadequately fixed battery is a fail. The risk is of it shorting and setting fire to the vehcle, with the slightest of accidents.
Yes, from the manual.....


DefectCategory
(a) Electrical wiring:

(i) insecure or inadequately secured
(ii) insecure and in contact with sharp edges or connectors likely to become disconnected
(iii) likely to touch hot or rotating parts, drag on the ground or the connectors for braking or steering disconnected


Minor
Major

Dangerous
(b) Electrical wiring:

(i) slightly deteriorated
(ii) so damaged or deteriorated it is likely to cause a short-circuit
(iii) for braking or steering components extremely deteriorated


Minor
Major

Dangerous
(c) Electrical wiring insulation:

(i) damaged or deteriorated
(ii) heavily deteriorated
(iii) in such a condition there is an imminent risk of fire or formation of sparks


Minor
Major
Dangerous

4.12. Not in use, Show​


4.13. Battery(ies), Show​








 
I have considered a plug and socket arrangement so I can easily put the car on charge. Wife's car used enough not to worry, but my cars can sit for weeks not being used.

With a smart charger, no longer is there a worry about over charging, it could remain on charge for months, well it does not really remain on charge, the charger takes the battery to 14.4 volts, then turns off, the voltage quickly decays to 12.9 volts, but that extra 0.1 volts it takes longer and longer as left on charge to hit 12.8 volts and the charger switches back on.

The mark space ratio seems to vary 1740825599455.png as it if caused by the car turning something on/off, or the battery is hard to say, but with an abandoned battery, I had to put another battery in parallel to get the smart charger to turn on, it was nearly two weeks before it started to charge. It was as if someone had flicked a switch, I was thinking it was a lost cause, when it displayed nearly the same charge curve as if only just been discharged.

It was a small battery for a stair lift, but it has since been repeated many times, and I have found a charge with a smart charger every few months does seem to extend the life of a battery, talking about a few days at least, not just until the charger says complete.

There may well be some parasitic drain, but the cure is to stop the drain, not simply fit a battery isolator. But
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I have always fitted to the negative, and quick release terminals
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do the same job, but today the boot is electric release, and the bonnet you need to get into the car first, to pull the release leaver, so one would need a method to open the bonnet. And it would disable so much, not sure if the engine management system will like being disconnected.

I am told I should charge the Jaguar battery from under the bonnet using the jump start spigot, as then the engine management system knows the battery is being charged.
 
I have fitted a proper battery cable extension lead, which fits onto the bolt on the end of the existing negative battery cable clamp, and then fitted heat shrink tubing around it, so there is now no way it can short, the heat shrink is at least 1mm thick and really solid, the only way to remove it is to cut it off with cable snips. I presume the kill switch itself won't cause an MOT failure? Meanwhile, I am trying to find an auto electrician who can fix the parasitic drain.
I am planning to fit another kill switch to my other car, which has no air conditioning, so I don't use it much during the Summer, so it's left idle for months at a time.
 
Well over a week, and my Kia is still taking the odd pulse of power into the battery.
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During Covid, the Jaguar did the same, and it reduced to once a day in the end. Really, it is time for it to come off charge, but I am being lazy.
 
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