Markokk888
Posts: 17
Joined: Wed Mar 21, 2018 4:16 pm
Delivery Date: 21 Mar 2017

Re: Active 12v to interior.

Sun Mar 25, 2018 6:45 pm

LeftieBiker wrote:
Markokk888 wrote:Well thanks for the advices but is there any big reasons to worry that much ? what can possible happen is i drain the 12v battery dead and that's it.


That's it if you don't mind replacing 12 volt batteries like wiper blades. Oh, and when the 12 volt battery fails it can take the brake assist with it, and/or strand you on the road.


Well i'm not stupid and i will not stress a small battery that is meant running basic systems that much. I just needed basic overall so i can make my own opinion on things. I understand what you are saying no need to joke like this. its nothing to do with a brakes.. Even if there is a some critical systems that needs power from a 12v battery it will get it from the dc/dc converter in any case. What do you will say next that the car will turn into dinosaur after you remove the battery lol :D sesh..

LeftieBiker
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Delivery Date: 31 May 2013
Location: Upstate New York, US

Re: Active 12v to interior.

Sun Mar 25, 2018 8:09 pm

I understand what you are saying no need to joke like this. its nothing to do with a brakes.. Even if there is a some critical systems that needs power from a 12v battery it will get it from the dc/dc converter in any case. What do you will say next that the car will turn into dinosaur after you remove the battery lol :D sesh..


You are expecting safe, logical engineering from Nissan. Guess again. The brakes can indeed fail with the car on if the 12 volt battery dies. It SHOULDN'T happen, but it does. You also expect the car to keep a larger 12 volt battery fully charged, and it may indeed do that. Or not - we'll have to see. The 2013 Leafs don't do that at all well, while the 2015 cars do.
Scarlet Ember 2018 Leaf SL W/ Pro Pilot
2009 Vectrix VX-1 W/18 Leaf modules, & 3 EZIP E-bicycles.
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

Markokk888
Posts: 17
Joined: Wed Mar 21, 2018 4:16 pm
Delivery Date: 21 Mar 2017

Re: Active 12v to interior.

Sun Mar 25, 2018 9:06 pm

Yeah it will stop working if someone will drink my brake fluid :D still doesn't make any sense what you are trying to say. Maybe ABS or a brake assist can stop working properly which i don't think but still in any situation you will still have your foot. 12v battery doesn't make your brake pedal to drop dead. Btw my leaf does not have a brake assist it would be a nice feature to add. Your brakes will work even if you will half strip your car and remove any batteries from it. As long as the brake lines ar fine. It will work.

LeftieBiker
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Delivery Date: 31 May 2013
Location: Upstate New York, US

Re: Active 12v to interior.

Sun Mar 25, 2018 10:05 pm

12v battery doesn't make your brake pedal to drop dead. Btw my leaf does not have a brake assist it would be a nice feature to add. Your brakes will work even if you will half strip your car and remove any batteries from it. As long as the brake lines ar fine. It will work.


I understand that you think you are on solid ground, here. What you say does make sense for any typical hydraulic brake system. The Leaf, however, is not typical. Maybe some kind soul will give you some links to brakes failing in the Leaf - foot to the floor failing, albeit with a little braking at the floor.

Here you go: http://www.mynissanleaf.com/viewtopic.php?t=18283
Scarlet Ember 2018 Leaf SL W/ Pro Pilot
2009 Vectrix VX-1 W/18 Leaf modules, & 3 EZIP E-bicycles.
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

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RegGuheert
Posts: 6199
Joined: Mon Mar 19, 2012 4:12 am
Delivery Date: 16 Mar 2012
Leaf Number: 5926
Location: Northern VA

Re: Active 12v to interior.

Mon Mar 26, 2018 3:06 am

Markokk888 wrote:Yeah it will stop working if someone will drink my brake fluid :D still doesn't make any sense what you are trying to say. Maybe ABS or a brake assist can stop working properly which i don't think but still in any situation you will still have your foot. 12v battery doesn't make your brake pedal to drop dead. Btw my leaf does not have a brake assist it would be a nice feature to add. Your brakes will work even if you will half strip your car and remove any batteries from it. As long as the brake lines ar fine. It will work.
Starting with the MY2013 LEAFs, Nissan switched to a mechanical accumulator to assist with braking force. (And, yes, ALL LEAFs have some method to assist with the braking force needed to stop the car since doing that with just your foot with four disc brakes is quite difficult.) But in the MY2011s and 2012, there was a 12-V ultracapacitor to assist with braking force. If that ultracapacitor was not fully charged to nearly 12V, the vehicle would COMPLETELY lose the brake pedal and it would move all the way to the floor with little effort. Low voltage could be caused by a low battery or you could have a fully-charged battery, but the capacitor was discharged for service.

The latter case happened to me. I took my LEAF in for a service bulletin to reprogram the braking computer. They completed the service in about an hour but the would not return the vehicle to me because they said it had no brakes. I asked what they meant by "no brakes" and they said there was no pedal. The guy sat in the car pushed the pedal all the way to the floor with ease. They gave me a loaner car for the weekend and the ultracapacitor had recharged by Monday and all was well.

Since that time I have been diligent to keep the 12-V battery fully charged.

I believe the MY2013-2017 LEAFs cannot have the problem mine had due to the ultracapacitor, but I suspect they can still have the same issue due to a low battery voltage since it appears to result in communications issues with the braking computer over the CAN bus.
RegGuheert
2011 Leaf SL Demo vehicle
10K miles: Apr 14, 2013, 20K miles (55.7Ah): Aug 7, 2014, 30K miles (52.0Ah): Dec 30, 2015, 40K miles (49.8Ah): Feb 8, 2017, 50K miles (47.2Ah): Dec 7, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

GerryAZ
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Location: Phoenix, AZ

Re: Active 12v to interior.

Mon Mar 26, 2018 5:29 am

My 2011 had and my 2015 has braking available with no power assist. On both cars, the pedal goes NEARLY to the floor and it takes a LOT of pedal pressure to stop the car (or keep it from moving on a slope). The LEAF, like most modern cars, has numerous computers that communicate over the CAN Bus network. The DC-DC converter will generally keep the 12-volt system at appropriate float voltage with the car in READY mode (green car symbol with arrows on dash), but a discharged or defective 12-volt battery can cause many issues (and DTC error codes) when trying to start the car. The communication errors can cause malfunction of the ABS system, brake power assist, etc. and prevent the car from going into READY mode. It will require a booster battery to get the car started and into READY mode if the 12-volt battery is discharged enough to cause CAN Bus communication errors.

I use my car as a portable office once in a while (powering stuff from the 12-volt system), but I always keep it in READY mode so the DC-DC converter and the HVAC systems remain active. The DC-DC converter should easily handle your 12-volt power needs as long as the car is in READY mode.
Gerry
Silver LEAF 2011 SL rear ended (totaled) by in-attentive driver 1/4/2015 at 50,422 miles
Silver LEAF 2015 SL purchased 2/7/2015

Markokk888
Posts: 17
Joined: Wed Mar 21, 2018 4:16 pm
Delivery Date: 21 Mar 2017

Re: Active 12v to interior.

Tue Mar 27, 2018 3:24 am

Well interesting topic. thanks for your advices.

arnis
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Re: Active 12v to interior.

Tue Apr 10, 2018 1:47 am

Like most modern vehicles, 12V is cut from everywhere further in the line.
You need to tap closer to the 12V battery. With a fuse (don't burn your car down :lol: )
Leaf's battery can give you 10-15Ah of energy safely with ignition off and car is not charging.
So one amp for one night (dashcam takes that much).
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