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Kia E Niro 4
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I appreciate that if you go into accessory mode you are running the radio etc on the 12V whereas switching to Utility it runs from the Main traction battery, or else that charges the 12V I would imagine. I don't really see the point of going into utility, why not when you pull up just leave it in normal mode as the radio etc will work and presumably the system will top up the 12v as required. Is there a difference in current consumption between normal or accessory or utility modes.
 

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I appreciate that if you go into accessory mode you are running the radio etc on the 12V whereas switching to Utility it runs from the Main traction battery, or else that charges the 12V I would imagine. I don't really see the point of going into utility, why not when you pull up just leave it in normal mode as the radio etc will work and presumably the system will top up the 12v as required. Is there a difference in current consumption between normal or accessory or utility modes.
I understand the consumption is less in utility mode - but perhaps Peter Prawlin can explain in more detail. It does have the advantage that no one can put the car into drive - accidentally or otherwise - and move the car.
 

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Kia e-Niro 4 MY20, Zoe Z.E.50 GT Line
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I haven’t checked but it’s likely some things are switched off in utility mode. It’s also not possible to accidentally engage drive which might be a concern in some circumstances.
 

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E-Niro 64kWh '4' since 9/20 (was Prius)
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@artyman I'm not entirely sure what you are asking but a summary of the modes and my general opinions is....

Normal READY to drive mode, 12V battery will charge when and if the 12V BMS thinks it needs charging. If it thinks it is at 100%, it tends to just float the battery at ~13V (neither charging nor discharging). If it thinks it needs charging, it charges at ~14.7V. I believe it doesn’t always get it right, hence why these cars don’t seem particularly great at recovering an accidentally discharged 12V battery even with a long driving session. However, once it’s fully charged it seems to maintain it adequately well just with normal driving.

Utility mode applies 14.7V continuously, so the aux battery gets a thorough charge session as long as in this mode. AFAIK, everything works except the actual driving shifter selector knob. The 12V battery will not get discharged at all whilst in this mode.

Accessory mode is horrible and I recommend it literally never used for anything. The 12V battery is quite heavily discharged whilst in this mode, and will never get charged at all whilst ever it’s in this mode. It isn’t just the stereo which is powered on but loads of other systems are also drawing significant power from the 12V battery. After just a few minutes you will get a battery warning. Even worse, it may take a long time to fully recover it back to a healthy full SOC.

If I was parked up and wanted stereo etc on, I would probably just start the car to normal READY mode but leave it in P (as it’s easy and convenient). Utility mode is great, but you have to jump through a few hoops to enable it. Also you have to turn car off and on again, in order to drive it. Utility mode is the best way to give the 12V battery a good charge top up, but it needs a few hours be sure of getting a full charge.

To answer your last sentence, Accessory mode heavily drains the 12V battery but applies zero drain to the traction battery.
Utility mode does draw a bit less power from the HV battery than does normal READY mode. But either can be on for many hours with very little impact on the traction battery SOC. I did measure it but can’t remember the actual numbers.
Peter
 

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utility mode is just for cases where you need battery, and you don't have intention to drive. I think that even in the owner's manual, it was mentioned that a good use-case is for example for camping.
 

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E-Niro 64kWh '4' since 9/20 (was Prius)
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utility mode is just for cases where you need battery, and you don't have intention to drive. I think that even in the owner's manual, it was mentioned that a good use-case is for example for camping.
Correct. The clue is in that modes title 😊

However it was discovered some time ago that an undocumented but extremely useful purpose for it is to properly top up the 12V battery without any need for using external mains powered 12V chargers.
Peter
 

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If utility mode switches off the headlights and DLRs, it will be useful for someone like me who sometimes gets back in the car (someone waiting in the car) and forgets to turn the headlights on.
 

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Utility mode uses include:
  • Charging 12V battery when it's showing "Caution" in UVO
  • Playing with headunit settings
  • Upgrading headunit software
  • Sitting in car waiting for e.g. picking up someone or for partner to nip in a shop
 

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Kia e-Niro 4 MY20, Zoe Z.E.50 GT Line
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Slightly confusingly, the car has to be fully powered on for utility mode to be available. You can’t activate it from accessory mode.
 

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Kia Soul EV
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Does the DRL is on in Utility mode? If it is off, then it would be useful for drive in cinemas, if you are waiting a long time in a car park...
 

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Does the DRL is on in Utility mode? If it is off, then it would be useful for drive in cinemas, if you are waiting a long time in a car park...
I would think they will be off, providing lights are turned off on the stalk switch and maybe also if the parking brake is set to on. It should be very easy to verify with a simple test? It would be somewhat whacky if the driving lights were turned to on when using a mode in which driving is impossible :unsure:

I would think a drive in movie would be the perfect application for Utility mode. HVAC (quietly and obviously without any exhaust emission) keeps you comfy whist your 12V battery gets a beneficial healthy maintenance top up. Only downside might be all the dash screens etc being illuminated.... perhaps you could dim them right down, or cover over with a towel or similar?
Peter
 

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Does the DRL is on in Utility mode? If it is off, then it would be useful for drive in cinemas, if you are waiting a long time in a car park...
No.
 

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I appreciate that if you go into accessory mode you are running the radio etc on the 12V whereas switching to Utility it runs from the Main traction battery, or else that charges the 12V I would imagine. I don't really see the point of going into utility, why not when you pull up just leave it in normal mode as the radio etc will work and presumably the system will top up the 12v as required. Is there a difference in current consumption between normal or accessory or utility modes.
You can also leave the car securely locked in utility mode (e.g. with heater/aircon running) so you have a warm/cool car (cool dog) on your return...... Set Utility Mode and HVAC, lock all doors with driver's door button, open driver's door and exit, close driver's door and lock it using the physical key (quarter turn anticlockwise). On return, again use the physical key in the door lock (remote will not work).
 

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KIA Soul EV 64kWh
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You can also leave the car securely locked in utility mode (e.g. with heater/aircon running) so you have a warm/cool car (cool dog) on your return...... Set Utility Mode and HVAC, lock all doors with driver's door button, open driver's door and exit, close driver's door and lock it using the physical key (quarter turn anticlockwise). On return, again use the physical key in the door lock (remote will not work).
Or use UVO to lock/unlock
 
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