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Kia e-Niro FE
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Discussion Starter · #1 ·
Since April 2020 I have monitored the 12V battery with the BM2 monitor. As we all know if the car is left unused it is given a 20 minute charge from the main battery every 24 hours. This has worked faultlessly until recently.
18th Nov I drove the car.
19th Nov there was no 20 minute charge. The voltage dropped from 12.71V to 12.59V.
20th Nov there was no 20 minute charge. The voltage dropped from 12.59V to 12.58V.
21st Nov I drove the car.
Since then the charging has gone back to normal.
Could this be a reason for 12V battery problems I wonder?
 

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Since April 2020 I have monitored the 12V battery with the BM2 monitor. As we all know if the car is left unused it is given a 20 minute charge from the main battery every 24 hours. This has worked faultlessly until recently.
18th Nov I drove the car.
19th Nov there was no 20 minute charge. The voltage dropped from 12.71V to 12.59V.
20th Nov there was no 20 minute charge. The voltage dropped from 12.59V to 12.58V.
21st Nov I drove the car.
Since then the charging has gone back to normal.
Could this be a reason for 12V battery problems I wonder?
The BM2 is a must have item for Kona/Nero owners.

John.
 

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E-Niro 64kWh '4' since 9/20 (was Prius)
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@Fred Gray ....... I’m sure you know that 12.6V after a couple of days is still very healthy of course. Especially so in this colder weather when the terminal Voltage drops slightly anyway due to temperature. Your battery is likely still at or very near 100% SOC.
I don’t think it’s a fault. Who knows how the algorithm works? I left mine unused for several weeks once. It stopped doing the daily 20 minutes top up after about 12 days. Then it suddenly did another one a full week later. I suppose it might depend upon what the BMS thinks the SOC actually is. It seems that the draw from the 12V battery is extremely low once parked up though I’ve not measured that, yet. I’m guessing it will be less than 10mA judging from how well the voltage holds up even when it’s not doing the daily top up thing.

The BM2 is so good it ought to be standard fitment on these cars (in fact on all cars!)

Peter
 

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Discussion Starter · #4 ·
[I don’t think it’s a fault. Who knows how the algorithm works? I left mine unused for several weeks once. It stopped doing the daily 20 minutes top up after about 12 days. Then it suddenly did another one a full week later.
Wouldn't it be great if Kia allowed us to know how the algorithm works so we would know if it is working correctly. No way that would happen of course.
 

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EU base model with heat pump Sept '18
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...Could this be a reason for 12V battery problems I wonder?
My Kona (still on the original BMS firmware until tomorrow) has never missed a 20 min daily aux battery charge since I installed the BM-2 nearly a year ago, even over 5 weeks of lockdown in March when the car was not used and I did not charge the traction battery. My early version base model (Irish spec) doesn't have the app functionality and the aux battery voltage is always between 12.8 and 13.1 in between charges.

Is there no sign of the car even waking up at the scheduled time?
 

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The BM2 is a must have item for Kona/Nero owners.

John.
Can you enlighten me please as to what the bm2 monitor is and why it is needed on the e-niro/kona?
 

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On those two days the car stayed fast asleep.
That is odd as in my understanding as to how it works the "system" (specifically the BMS) must wake up to digest the contents of the battery sensor and make a calculation as to the aux battery's SoC. That's leaves a telltale glitch on the BM2 graph, similar to what you get when opening a door.
These cars do have mysterious ways and I can hardly wait to see what drama the dealer inflicts tomorrow on my so-far perfectly-operating EV.
 

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Can you enlighten me please as to what the bm2 monitor is and why it is needed on the e-niro/kona?
It's a small Bluetooth device that connects to the 12V auxilliary battery to monitor its state of charge. There's an app for your phone/tablet that downloads the data and can show you the state of charge over time. A number of Kona and Nero owners have experienced dead 12 volt batteries, which obviously prevents you using the car, or even getting in it without the key. As yet, the cause of a dead battery is unknown - but there's lots of speculation.

Hope this helps.

John.


NB other marketplaces are available.
 

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It's a small Bluetooth device that connects to the 12V auxilliary battery to monitor its state of charge. There's an app for your phone/tablet that downloads the data and can show you the state of charge over time. A number of Kona and Nero owners have experienced dead 12 volt batteries, which obviously prevents you using the car, or even getting in it without the key. As yet, the cause of a dead battery is unknown - but there's lots of speculation.

Hope this helps.

John.

[/URL]

NB other marketplaces are available.
Ahh, ok, thanks for the info, I'll check it out.
 

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Discussion Starter · #11 ·
....That's leaves a telltale glitch on the BM2 graph, similar to what you get when opening a door.
Yes the graph does show tiny voltage oscilations. I hadn't thought it was worth mentioning previously. The biggest one on 19th Nov was 12.62V at 6.07am and 12.70 at 6.09am. Perhaps there are systems running in the background like the alarm.
 

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E-Niro 64kWh '4' since 9/20 (was Prius)
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My Kona (still on the original BMS firmware until tomorrow) has never missed a 20 min daily aux battery charge since I installed the BM-2 nearly a year ago, even over 5 weeks of lockdown in March when the car was not used and I did not charge the traction battery. My early version base model (Irish spec) doesn't have the app functionality and the aux battery voltage is always between 12.8 and 13.1 in between charges.

Is there no sign of the car even waking up at the scheduled time?
Unlike yours, During a long period of complete disuse, mine went a full week without any daily 12V auto charging occurring once. No sign of any wake up or glitch etc. Just a very steady healthy flat line Voltage. Then it mysteriously resumed its daily top up on the 2nd November.....
Peter
138531


138532
 

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I get the impression that your battery could use a charge, perhaps 1-2 hours. I can't explain the 2 Nov with no wake-up.

This is what I'm seeing now, a check every 4 hours and an occasional 20 min charge. You can see there's no voltage-based reason for the charge on this particular day. The sensor on the negative terminal is how the BMS monitors the SoC and it doesn't always seem entirely foolproof. Before the update I used to see a droop to about 12.8 V between daily charges. There's no "app" functionality on my Kona, FYI.

138647
 

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Yours is certainly sitting at a higher resting Voltage. Mine might be in need of a bit of a charge as I’m really not using the car much due to lockdown etc. Also please remember it’s winter here with typical temps around 1 to 6°C. I assume you’re at 20°C or more? That definitely affects the terminal Voltage available. I might try the utility mode thing for a few hours soon. Actually, the forecast is unusually warm tomorrow at 13°C so I’ll probably capture the Voltage before I try topping it up. See what effect the temperature rise alone has.

Peter
 
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Yesterday I did a 5.5 hour Utility Mode 12V maintenance stint as suggested by @KiwiME . I also left my iPad inside the car with Car Scanner app recording some data from the OBD2. I locked the car via UVO app. I think the results speak for themselves. The 12V battery is now sitting at a higher resting terminal Voltage as seen on the BM2 24h capture chart.

The only thing I don’t understand is the 12V SOC value. The 12V BMS in the car seems to think it’s still only at 80% even after this charging session. I feel it is actually very close to 100% in reality. In fact whenever I’ve been playing with the Car Scanner app, I’ve never seen the 12V SOC go significantly above 80%. I could have let it run for a few more hours as the charging current was still slowly decreasing, but I think the further benefit would have been tiny and not really worth it. The air temperature yesterday was unusually mild at around 12°C.

Peter

BM2 chart.......
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OBD2 data.......
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Possibly you should treat the displayed Aux Battery SOC with a little caution.

I have used Car Scanner with my Kona and find it a nice UI. I have also used TorquePro which allows the OBD PIDS to be modified.
You may be aware that the Kona and Niro OBD PIDs which can be used in TorquePro were developed by an occasional poster in these forums - JeJuSoul who originally worked on them for his Soul EV and subsequently posted them to the github web site with the strong belief they are also applicable to the Kona and the Niro.
I am not criticising the work done by JejuSoul - he has provided are an oustanding example of technical investigation
followed by freely sharing with anybody interested.

My suspicion is that the Car Scanner app also uses these PIDs for the Kona and for the Niro.
A clue is the Aux Battery current value which the 'original' PID with TorquePro gave the result fof about 32 amps for my Kona, but another user subsequently devised an alternative equation for the PID which gives a much more realistic value.

I see similar numbers using Car Scanner with my Kona - the two values presented as - Auxiliary Battery Current of 32 amps and the var.2 value which is much lower. As shown for your Niro.

My conclusion is that it is very likely that Car Scanner has used the same original PID equations (plus an amended version for Aux Battery current) as provided by JejuSoul who quite recently stated in post #761 in the Kona thread 'Just an Update on My Charging Issues' : 'I don't have a Kona EV so have never tested the OBD PID codes. They are just copies of the codes we developed for the original Soul EV.'

To me, all the OBD numbers are good indicators but not necessarily completely reliable.
 

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Do you have a source for the pid alternatives to jejusoul? I'm particularly interested in the Aux Battery info.

Sent from my Pixel 3a using Tapatalk
 

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Do you have a source for the pid alternatives to jejusoul? I'm particularly interested in the Aux Battery info.

Sent from my Pixel 3a using Tapatalk

See this post in another forum from hobbit Jan 26 2020 giving a suggestion for a revised version of Aux Battery Current

My trial of this suggested the numerical result is approximately correct but perhaps the magnitude is too high by about 0.4 amps.
If you are using TorquePro, the battery charge/ discharge in coulombs over time can be recorded and displayed by using the TorquePro TOT function, applied to the value of this current.
 
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