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@Richard Gledhill , you may be right but based on my experience I suspect it is something different.
My Kona ended up with flat battery 4 times in last 6 weeks. In those 6 weeks it always occurred after driving the car and then short parking (anything between 5 minutes to 1hr).
When in DRIVE mode the battery should be topped up. It shouldn't get discharged so quickly no matter what.
It looks like 12v battery doesn't tell the car it needs to be recharged. DC-DC is still probably engaged as all lights are fine and there is no issue with low voltage electrics. But after parking for a few minutes the battery is flat. It looks like it was not topped up at all.
My Huyndai did something with 12v calibration and said that everything is fine. Yet 10 days later we have flat battery again.
Off to dealer on weekend again...
 

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Once again my battery has gone flat, plunged down to 3.3v . I drove it for 70 miles yesterday so I've no idea why this is happening? Off down the dealers in the next few days I reckon.

128221


edit: I've jump started it and noticed one of the reading lights was in the on position. The light goes out after the car is locked but maybe it confuses the software?
 

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I sat in mine with the voltmeter on to check what happened when switching off and locking. The ECU shuts down power to everything after a short while so having the light switched on or off seems to be irrelevant.

Is this the same battery that went flat before? If so, how did you bring it back to life? 12v doesn’t like deep discharge so is likely US by now if this has happened several times already.

What’s the reading on that current draw?
 

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I sat in mine with the voltmeter on to check what happened when switching off and locking. The ECU shuts down power to everything after a short while so having the light switched on or off seems to be irrelevant.

Is this the same battery that went flat before? If so, how did you bring it back to life? 12v doesn’t like deep discharge so is likely US by now if this has happened several times already.

What’s the reading on that current draw?
Same battery. I just put a small lithium jump starter across the battery points. Twice I've done that now and it starts, jumps up to around 14v then when I switch the car off drops to 12.7v and gradually declines from there. Last night from 12.7v at 10pm it is now on 11.3v at 11am,
 

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That suggests to me that the battery is no longer holding charge but the only way to be sure is to put it on a mains battery charger and bring it back up to full. I don’t think the charging circuit in the car is robust enough to do that job in relatively short bursts of driving.

Can’t recall the exact figure but think mine was a 45ah battery when I looked a while ago. Assuming your graph was showing a constant 2 amp draw, it should still last a day before completely giving up.

But the issue is more that current draw, 2amps at 12volts nominal is a constant 25watt consumption. There is no way that any car should be drawing that much power when locked on standby even with alarms on. There was a comment made earlier on the thread regarding the ECU not shutting down which sounds like it could be relevant.

That sounds like an errant circuit somewhere drawing power when it shouldn’t be. Could try pulling some main fuses and watching what happens maybe but think I’d be phoning Kia to get them to diagnose it. Just make sure you’ve got no accessories in the car which they can blame, cos that’ll be their first plan to fob you off.
 

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They need someone to wire up diagnostics to the ECU communications buses and just repeatedly turn the car on and off again until they notice that things aren't shutting down properly, then see which ECU is still awake and check its logs.
 

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Don’t think mine is when it’s not charging. Pretty sure it dies soon after the system shuts down the lighting etc once locked. Have to double check to make sure though.
 

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It turns the OBDII port after about 15 minutes, unless it's actively charging.
 

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@Richard Gledhill ,
I think there is more than one pin that supplies energy to OBD. When my battery went flat and the car would not start anymore my OBD dongle (Torque Pro) was still powered on when I plugged it in.
But my second OBD dongle (Voltmeter with extra USB ports) goes down a few seconds after powering off the car. I bought OBD voltmeter to check how low the voltage has gone when car appears dead (usual cigarette lighter socket is off when the car is off). Sadly OBD never works that way - only when car is ON it receives power.
But OBD dongle for Torque Pro must be using another circuit.

Last Saturday my 12v battery went dead again - twice. It was dead in the morning so i jumpstarted the car. Drove to shop (should recharge a bit and / or Aux battery saver should kick in afterwards) but it died when i returned 3 minutes later. It looks like the battery doesn't tell the car it needs recharging.
Jumpstarted the car again and then drove to multiple places and the car worked fine. So the car has mind of its own when to charge / not charge the battery. Annoying!
The same happens to my dashcam installer who has e-niro.
 

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OVMS is definitely still running when the car is powered off. I'm going to take it in to the dealer this week. Let's see what they say.
 

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Interesting, my OBD2 port is definitely dead exactly 15 minutes after I lock up. Good luck at the dealer..
 

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Ah, the joys of lockdown, my 12v is permanently on the maintenance charger currently so hoping it does a good job of sorting out the battery for the long term!
 

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Ah, the joys of lockdown, my 12v is permanently on the maintenance charger currently so hoping it does a good job of sorting out the battery for the long term!
Could you explain maintenance chargers? Do you have to have the car in a garage to use one? I'm not very up on this kind of thing.
 

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Could you explain maintenance chargers? Do you have to have the car in a garage to use one? I'm not very up on this kind of thing.
I don't understand the chemistry of how they work but they are designed to bring the battery back up to full and then condition / maintain it at that level without overcharging. Mine isn't in the garage, it's on my driveway. Small extension lead plugged in under garage door, with supply lead fed into the engine bay via the rear of the bonnet opening near the scuttle. Extension cable and charger unit sat safely (and dry) out the way under the closed bonnet with charger leads securely attached to the 12v terminals. Car is locked so will still be using some electricity but the point is to make sure the 12v is fully topped up rather than anything else.

The reason I wanted this solution was the car is likely to be sat for days on end and I didn't want to risk discharge given what's been reported by other EV owners (y)
 

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Does anyone see any advantage to flicking the 'Fuse Switch' on the driver's knee fuse board during a couple of month's estivation (similar to hibernation but in the summer)?
 
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