[matt_g]

Hi Folks,

So my Jimny occasionally sits for a week or two, and in winter this was killing my battery, so I decided to get a trickle charger, with the connector that stays wired to the battery. The charger is a CTEK MXS 5.0.

Now, whether this is a coincidence or not... since I first (and only) used it, I've noticed my car's door locks have become very enthusiastic about auto-locking themselves. The vehicle has an alarm fitted to the central locking (from the dealer when new), so when you lock or unlock with the key fob, you have a squeak or double squeak from the alarm's siren. The central locking (when you just use the key in the door lock) locks the doors, but doesn't arm the alarm.

The symptoms appear to be - when I unlock / disarm the alarm, and don't open a door, it re-locks and leaves the alarm disarmed. If I unlock / disarm, open a door, close it and leave the door unlocked, it will re-lock itself automatically, but not every time.

Also, the interior light is occasionally not illuminating when a door (including the tailgate) is opened. Toggling the switch in the headliner doesn't cause it to come on, but if I press the rubber sensor nipple in and release it, the light will come on.

So, could the charger have introduced an electrical gremlin to my system, or could the mechanic have done anything in fitting the connector during my last service to cause this?

I'd be inclined to blame the keyfob (and I'll try a battery replacement because I have a sense that the unlock button is less often working first go), but the cabin light issue seems to contradict that.

Any ideas?

Thanks.

[MightGetDirty]

Hmmm does this happen when the trickle charger is still on/plugged into the mains or even when it is "off" and you are out and about?

I am going to take a stab at this without much research/evidence and suggest to check whether it is a grounding issue - inspect and clean up the main ground wire from your battery to the car body (or even replace it entirely with a new lead) and see if that helps.

I've been reading around for my GV3 that sometimes, the OEM grounding somehow isn't the best or that over time it is degrading, and that is creating some voltage issues such as slower/poor starts, poorer economy and so on. Most people get by with simply getting a newer, stronger battery but I suppose that won't work for you (strong batteries still go flat after non-use) so changing the ground wires could help here.

Trickle chargers tend to do additional functions when on to help increase the health of the battery when idle.. so my theory is that if these gremlins are happening to you while it's on, these health maintenance cycles + poor grounding is creating voltage fluctuations throughout the whole vehicle which some of your systems are a bit more sensitive to.

[matt_g]

Hey thanks for the reply.

I go through a battery every ~3 years, after my original battery lasted around 5. Granted, I drive the car maybe once or twice a week, and sometimes it goes a couple of weeks without being driven. Hence why I thought to invest in the charger.

The problem I'm having occurs when the car isn't connected to the charger - I've only used the charger the one time, but the coupling is still wired in.

Attachment:

battery_wiring.jpg

The instructions state for batteries mounted inside the vehicle, that the black clamp should be mounted to the vehicle chassis remote from the fuel pipe and battery. I assume that's referring to the earth connection? The diagram shows the "comfort connect" as they call it, for permanent connection should be wired to both the battery terminals.

I conducted a test this morning: Unlocked / disarmed with my key fob, opened the driver's door, closed the door. Around 10-20 seconds later, the central locking engaged and all the doors locked. The alarm was not re-enabled, which makes me think it's not the keyfob that's malfunctioning, because it always interacts with the alarm...

...as an aside I did disassemble the keyfob last night, to eliminate it as a possibility, and the microswitches on the circuit board for the lock / unlock buttons were completely gummed up and half encased as what can only be described as verdigris green "matter". After an hour of so of spraying with isopropyl, and working the switches, and a seemingly endless supply of green goo coming up out of the switches, like a teenager's face, they seem to be clear and clicking responsively. So the key reassembled, I tried today's door lock / unlock experiment.

I don't have experience with car electrical systems, so if I want to remove the charger coupling to see if that's the problem itself, should I disconnect, remove, reconnect one lead, then the other (black or red first), or loosen them both off at once?

All I can recall about each time the battery was replaced, was that I had to re-set the stereo.

The only other modification the car has that could interact with the electrics, is an FM modulator, wired to an on switch, and a stereo minijack. But that's been in the car since new.

Cheers,

[MightGetDirty]

matt_g wrote:

The problem I'm having occurs when the car isn't connected to the charger - I've only used the charger the one time, but the coupling is still wired in.

Attachment:

battery_wiring.jpg

From the looks of your photo, the charger lead hanging loose like that shouldn't affect much of anything as it's an open circuit.. I'm kind of doubting the charger to be the issue now TBH.

matt_g wrote:

The instructions state for batteries mounted inside the vehicle, that the black clamp should be mounted to the vehicle chassis remote from the fuel pipe and battery. I assume that's referring to the earth connection?

I would assume so too, "remote" being "away" from the fuel pipe/hose lines and battery sounds like the most logical interpretation.

matt_g wrote:

I conducted a test this morning: Unlocked / disarmed with my key fob, opened the driver's door, closed the door. Around 10-20 seconds later, the central locking engaged and all the doors locked. The alarm was not re-enabled, which makes me think it's not the keyfob that's malfunctioning, because it always interacts with the alarm...

THIS sounds interesting though..

I'm not sure of the electronic system behaviors for the 3rd gen Jimnys and whether they have any similarities to those in the GV3, but I would check your owners manual for how the "keyless entry" function works and check just how often your drivers/other door switches are working correctly or get stuck in the "closed" position (you mentioned your interior compartment lights not turning on, but I didn't think much of it until just now)

For my GV (which is more-or-less from the same era as yours), the owners manual states that if no door is opened "about 30 seconds" after the unlock button on the keyfob is pressed, the doors will automatically lock again. This sounds pretty close to what's happening for you (assuming opening and closing your drivers door takes ~10-15secs). Then, because the automatic locking is controlled by the BCM, it might not trigger the activation of the car alarm.

You may be in need of cleaning door switch contacts if you can't replace them altogether as it sounds they aren't closing the circuit reliably when the doors are truly open and causing this strange behaviour.

[matt_g]

MightGetDirty wrote:

You may be in need of cleaning door switch contacts if you can't replace them altogether as it sounds they aren't closing the circuit reliably when the doors are truly open and causing this strange behaviour.

Ahh. Are you thinking perhaps that the central locking is never receiving the signal that the door has opened (which is indicated by the cabin lights not illuminating), and therefore the doors re-locking is a doors-not-opened-so-relock situation?

[MightGetDirty]

Yes!

I'm a bit long winded with my answering sometimes. Whoops

[matt_g]

MightGetDirty wrote:

Yes!

I'm a bit long winded with my answering sometimes. Whoops

haha, no worries, but this might have just become weirder / more complex; The (aftermarket I think) reversing sensors / distance beepers aren't activating either. I've only just noticed.

I'm wondering, could this be a fuse issue?

[matt_g]

Latest weirdness:

Keyfob unlocked / disarmed the alarm, cabin light illuminates. Open driver's side door, lean across to glove box, open and take out owner's manual, close glove box.

Straighten up, notice cabin light has gone out, the central locking locks all the doors, while the driver's door is still open. Toggling the cabin light control brings it back on, but the central locking won't respond to the unlock command on the keyfob. Closing the door causes the central locking to unlock, ad the keyfob can then lock the door.

Calling an auto electrician, or an exorcist today.