Kia Picanto parasitic battery draw

So let's say that I have unlocked the car with the keyfob, then I pull the boot handle - this somehow makes the reed switch break or make contact. This signal is sent to the car. Does it then think the boot is open? So if I lift the boot door up, and then pull the boot handle again, does it then think the boot door is closed? Surely it can't be anything to do with the switch under the boot handle, whether the car thinks the boot door is open or not?

I presume that in the mechanism that I saw behind the boot 'claw', the door lock metal rod and the central locking metal rod do something when they move, that then allows the door handle to open the boot. Otherwise (obviously) the door handle wouldn't unlock the 'claw', or you would never be able to lock the boot.

Jurassickpark, can you elaborate where the switch is, that has a hall sensor effect?

Old Salt - is the light switch on the metal bar thingy that pushes the 'claw' up and around it when you shut the boot? I haven't looked down there!
 

"The boot latch has a microswitch inside it. Over time the microswitch starts to fail. Failure is hastened as the boot struts wear because the boot starts to shut too heavily."

This is what I think must be happening in my Picanto, unless I'm completely wrong. First, I will look to see if there any electrical cables coming from the boot latch (what I called the 'claw'). If not, that's not the way the Picanto knows the boot is open or closed.
 
SenileGit said:
So let's say that I have unlocked the car with the keyfob, then I pull the boot handle - this somehow makes the reed switch break or make contact. This signal is sent to the car. Does it then think the boot is open? So if I lift the boot door up, and then pull the boot handle again, does it then think the boot door is closed? Surely it can't be anything to do with the switch under the boot handle, whether the car thinks the boot door is open or not?

I presume that in the mechanism that I saw behind the boot 'claw', the door lock metal rod and the central locking metal rod do something when they move, that then allows the door handle to open the boot. Otherwise (obviously) the door handle wouldn't unlock the 'claw', or you would never be able to lock the boot.

Jurassickpark, can you elaborate where the switch is, that has a hall sensor effect?

Old Salt - is the light switch on the metal bar thingy that pushes the 'claw' up and around it when you shut the boot? I haven't looked down there!
Click to expand...
I have only looked at a google response from the kia forum. The door/boot operated switches are usually just some form of plunger that makes and breaks an earth as the door/ boot is operated. I would be checking the frame around the boot to see if there are any similar looking mechanisms.

Is there a flap near the catch? They can be well hidden. Some photos may help.
 
This might be worth trying:


I didn't know that the latch was supposed to go that far up, I pushed mine with a screwdriver to the first position, thinking it was as far as it should go, and the dashboard light stayed on. Tomorrow I will try pushing it all the way up and see if the light goes out - then I know that I have to adjust the bar on the bottom of the door frame instead, as shown in the video - maybe that will fix it! I can see how the bar might get pushed forward into the car over time, if the door slams shut on it over and over.
This all presumes there is a microswitch in the latch in the Picanto, which I didn't think to check today while I was looking at it.
 
If you are going to adjust anything its worth marking the original position of both parts with a pencil so that you can get back to the start point if necessary. Only adjust one at a time and leave the bolts only slightly loose so that you can carefully make minor adjustments.
 
SenileGit said:
Yes, but what does it actually do when it makes the circuit? What happens in the car electronics? How can it tell the car that the boot is open, and thus cause the light on the dashboard to come on?
Click to expand...

It just tells the LSM, the electronics, to put the light on.
 
Harry Bloomfield said:
No, I don't think they even make them these days. There function is replaced by reed switches and magnets.
Click to expand...
I think they are still getable, but probably not in use in the automotive industry.
I just used it as a kind of generic term for tilt switch.
I remember playing with mercury on my desk, in science class.
We were mad as hatters in those days. :LOL:
 
Hi Old Salt, thanks for the video, I looked at the metal bar in the middle of the boot frame, but there are definitely no sensors there.
But I reconnected the battery, and pushed the 'claw' thing all the way in, as shown in the video I posted above - and the 'boot open' light turned off. I checked the area around the 'claw' catch mechanism, inside the boot door, after taking the plastic panel off, and there are definitely no cables going into it - so I believe the metal rod that attaches to the central locking motor is what tells the car that the boot is open. As the 'claw' is turned around, as the boot is closed, as the 'claw' goes around the bar, it must move the metal rod and change the position of the motor, or a sensor in the motor unit.
Anyway, I sprayed a second lot of WD40 into the lock mechanism, pushed the back seat down and shut the boot from inside the car, so I could look at the 'claw' mechanism, and it shut properly - I could see it had gone all the way round, and the 'boot open' light had gone off.
Originally I had tried to undo one of the Philips screws (very large) that hold the bar in place, but it was absolutely impossible to turn it, so I luckily gave up - luckily because I didn't need to adjust the bar's position.
I then opened and closed the boot about fifty times, each time watching the 'boot open' light on the dashboard, and it went off every time I shut the boot, so I think that problem is fixed. (I'm still not putting the bulb back in the internal boot light, in case the switch goes wrong again and flattens the battery again!)

BUT;
After fixing the 'boot open' warning light problem, I disconnected the battery again, and tested the current between the battery connector and the battery post, and I still got 0.3A for 60 seconds, then down to 0.01A. So the 0.3A is definitely nothing to do with the 'boot open' warning, which has now gone. I think it is something wrong with the immobiliser/central locking/security system. I think I will have to get an auto electrician to have a look at it. I should be getting my Japanese battery post adaptors tomorrow, so I will be able to fix my kill switch then, and at least then I can use the car as normal, without having to worry about the battery discharging, while I look for an auto electrician who can fix the parasitic draw.
So at least I've fixed the 'boot open' warning!
 
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SenileGit said:
So the 0.3A is definitely nothing to do with the 'boot open' warning, which has now gone. I think it is something wrong with the immobiliser/central locking/security system.
Click to expand...

I would expect the 300mA, initial discharge after switching things off, is perfectly normal - just your car's electronics shutting down gracefully, into sleep mode.

What is important, is the discharge when everything is asleep. That should be around 20 to 40mA. Can your meter measure that accurately?
 
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Harry Bloomfield said:
I would expect the 300mA, initial discharge after switching things off, is perfectly normal - just your car's electronics shutting down gracefully, into sleep mode.

What is important, is the discharge when everything is asleep. That should be around 20 to 40mA. Can your meter measure that accurately?
Click to expand...
I agree with Harry, modern cars like to drift off to sleep before shutting everything down.
 
Old Salt said:
I agree with Harry, modern cars like to drift off to sleep before shutting everything down.
Click to expand...

A Scorpio I once had, would take an entire month, before it went into its deepest sleep mode - The last thing it switched off, after a month, was the remote control receiver, for unlocking the doors. If left unused that long, you would have to use a key in the door, to unlock it.
 
I will have to attach my multimeter to the battery post and battery clamp with some clamps, so that I can leave them connected for several hours, and periodically check the multimeter readings. It goes down to 2mA, so it should be able to show what's happening.
It may be that now that I've fixed the boot door problem, that there is no more parasitic drain, I can but hope.
 
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.
 
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