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Renault Zoe Intens Q210 22kw 2013
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Discussion Starter · #1 ·
Just wondering how the DC-DC converter works to charge the 12v DC battery under the bonnet? - So i think it charges the 12v battery (if battery is low on voltage ) when the drivers door opens (and when you see the Zoe spinning on the dash) - so what does it do keep charging the 12v does it from then on even if you lock up the car again (until its fully charged at 13,8 volt or whatever it is?) -

the car has no 'alternator' like an ICE car so i am presuming whether driving for a while or not is irrelevant? - and it just takes its charge as and when it needs it ?

Also what happens when the car has gone to sleep and if the 12v battery drains (due to the ambient temperature outside) or if stuff trickle powered takes voltage from the battery to keep it alive - does the DC-DC converter topup the 12v battery then or does it just wait until the driver opens the drivers door to start driving?

Zoe 2013 Q210 ZE20
 

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I'm not crazy, the attack has begun.
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When the HV battery is active, the DC-DC converter is always putting voltage out onto the 12V line. When it isn't, it isn't.

I can't answer the next question, when the HV is or is not active, but you should hear a 'clunk' when the isolation relay closes and opens.

Whether the voltage that is put onto the 12V bus is enough, or not, is the key worry for modern BEVs. Software engineers who programme that output voltage don't appear to have received proper training on what makes a 12V battery work, or fail.

You should get a plug-in voltage readout, it is the only way in a BEV to monitor 12V battery health properly, you need to learn what is or is not normal for the car.
 

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Renault Zoe Intens Q210 22kw 2013
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Discussion Starter · #3 ·
When the HV battery is active, the DC-DC converter is always putting voltage out onto the 12V line. When it isn't, it isn't.

I can't answer the next question, when the HV is or is not active, but you should hear a 'clunk' when the isolation relay closes and opens.

Whether the voltage that is put onto the 12V bus is enough, or not, is the key worry for modern BEVs. Software engineers who programme that output voltage don't appear to have received proper training on what makes a 12V battery work, or fail.

You should get a plug-in voltage readout, it is the only way in a BEV to monitor 12V battery health properly, you need to learn what is or is not normal for the car.
thanks, yeah i must get myself one of those digital ones you plug into the cigarette lighter - be handy.
Imagine beinggreat with programming and manage to write new firmware for the TFT speedo screen and include present 12v battery voltage on the screen ... there is enough room on the screen for it. I would love to be able to hack it to do that
 

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Ioniq 5
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thanks, yeah i must get myself one of those digital ones you plug into the cigarette lighter - be handy.
Get a BM2 monitor - much better.

 

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Zoe R110 ZE40
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As far as I know, there is no automatic system that detects a low 12V battery, so turns on the car to begin charging it.

Cigarette lighter version wont work - as soon as you start the car, and so turn on the power to the cigarette lighter, the DC-DC convertor is activated, so you are detecting the convertor voltage, not the battery voltage.

The BM2 monitor listed above will always be turned on (as it is connected directly to the battery) so worth checking what its current draw is.
 

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I have the BM2 battery monitor and connected it about 5 days ago. I agree with the statement that you have to learn what is normal so that if you do get a problem you can make a comparison with when it was working correctly.
 

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The higher voltage spikes are associated with opening the door but not driving. The lower spikes are short journeys and the long pulse at 01/11 is overnight charging.
 

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2021 Corsa-e
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As far as I know, there is no automatic system that detects a low 12V battery, so turns on the car to begin charging it.

Cigarette lighter version wont work - as soon as you start the car, and so turn on the power to the cigarette lighter, the DC-DC convertor is activated, so you are detecting the convertor voltage, not the battery voltage.

The BM2 monitor listed above will always be turned on (as it is connected directly to the battery) so worth checking what its current draw is.
I think Teslas actively monitor the 12v, even when the car is "off". If it senses a low 12v, it will engage the DC-DC and charge it up.
I think some Hyundais also have some form of "offline" charging of the 12v (if I recall correctly from another thread here, it's time based, something like every 4 days it turns on, if the car hasn't been driven).

Other than those, most EVs charge the 12v only when car is powered on (HV battery engaged), using the DC-DC converter.

I also have the BM2 and it's standby consumption is pretty low (less than 100ma if I recall correctly). I haven't had issues with it draining the battery so far, even if the car hasn't been driven for a few days.
 

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Kia e-Niro 4 MY20, Zoe Z.E.50 GT Line
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The ZE50 does appear to charge the 12V battery, likely based on voltage.

Here you can see the pattern when the car is sitting idle, not plugged in.
 

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I'm not crazy, the attack has begun.
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View attachment 155537
The ZE50 does appear to charge the 12V battery, likely based on voltage.

Here you can see the pattern when the car is sitting idle, not plugged in.
That's not charging a 12V lead acid battery. That's slowly destroying it. Through sulphation.

Voltage needs to be at least 13.6V float voltage, whilst the battery forms part of an actively maintained 12V circuit.

This is the problem; whoever has programmed that thinks that by turning the charge rate right down periodically it is saving power out of the HV battery, giving more range.

Yep, it is adding an extra 50 yards whilst creating the circumstances for the battery to fail.
 

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Kia e-Niro 4 MY20, Zoe Z.E.50 GT Line
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Yes this is just an on/off. There’s no float charging going on as you say. Which will be why Renault have replacing the 12v battery as a service item I guess.

however, it is the case the charging circuit is engaged when the car is idle and not plugged in.
 

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Looking at both the ZE40 and ZE50 data, although they are quite different they both have the small negative spikes at roughly 8 hour intervals. Is this the car waking up after a set period to talk to the servers?

Andy, did you say that there was a parameter in DT4ALL that causes the car to wake up and activate the TIU? If it's in seconds it would be around 29,000.
 

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Renault Zoe Intens Q210 22kw 2013
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Discussion Starter · #16 ·
....Andy, did you say that there was a parameter in DT4ALL that causes the car to wake up and activate the TIU? If it's in seconds it would be around 29,000.
Here are the settings on the TCU in my Q210 2013 ZE20:
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Thank you for that but there doesn't seem to be anything there that corresponds to 8 hours or thereabouts.

I know certain events triggers an upload to the servers like starting the car, and periodic reporting when there is no activity. I think there is also an inhibit timeout to stop the car reporting to much if you continually started and stopped it presumably to cut down on the amount of data reaching the servers. I think this is going to take a bit of time to unravel unless someone has any documentation.
 

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Renault Zoe Intens Q210 22kw 2013
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Discussion Starter · #18 ·
Thank you for that but there doesn't seem to be anything there that corresponds to 8 hours or thereabouts.

I know certain events triggers an upload to the servers like starting the car, and periodic reporting when there is no activity. I think there is also an inhibit timeout to stop the car reporting to much if you continually started and stopped it presumably to cut down on the amount of data reaching the servers. I think this is going to take a bit of time to unravel unless someone has any documentation.
Not really sure i cannot find update to data frequency to the servers apart from the 16777215h EV status Data frequency update in the TCU settings there , and was wondering myself does that equate to 16hours update to servers ... or is it frequency as in hz frequency and not hours? - as 16hours might be more like it (update details from Zoe to servers every 16hours) - I am pretty sure I read further somewhere that if the TCU did update more frequently that not only would it take more power (presumably from the 12volt battery system) that if you did set it at a shorter amount of times it updates to their servers if you did set it too short durations (I dont know how short / what the threshold is) but that if you did shorten it and it did talk more often than it should they (Renault) could boot you off their servers! - I dont know if thats true but I think I recall reading something like that. - so thats where you have to beccareful setting those settings in the TCU section.

As for the other settings this is what I decipher them to mean (and of course i could be wrong)
Vehicle Definition= well that's self explanatory
EV BSOC Difference transmission= I would think 'report when battery(traction battery) state of charge is a difference of 5 (percent ?? )
EV Charge In Progress time-out= if type 2 charging plug is not plugged in by 30seconds then timeout?
EV SMS Waiting Time= wait for 5seconds before sending a text message to the mobile phone saying 'charging has started' ?
EV VSOC Transmission frequency 1800 = (something) State of Charge ? - but is the frequency time or frequency as in a radio frequency I am not really sure , but 1800 seconds equal 30minutes - or it may mean 1800mhz ??? - I dunno
EV Activation Time check= I am presuming the 31s is 31seconds
EV Wakeup frequency= wake up the car every 5 minutes its charging maybe?

Sorry I am so vague but as you can see I have been using DDT4ALL for well over a year on my Zoe and its still a learning curve with particular settings like this on the TCU ECU - i read a lot of sites and forum's but a lot of the times they are not in plain English or in a foreign language hard to decipher or forum members have just 'guessed' what these settings do. Normally if I have not got a near enough understanding of what the setting does I dont generally touch it in DDT - and as another security blanket is backup the original values of the ECU before I change them so I can roll back if problems happen or write down or take screenshots/ camera pics before making settings.
 

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EV BSOC Difference transmission= I would think 'report when battery(traction battery) state of charge is a difference of 5 (percent ?? )

That equates to about 8 miles in my 40 but I dont see reporting that often in the app but I'll look out for that next time we do a more substantial journey.

EV Charge In Progress time-out= if type 2 charging plug is not plugged in by 30seconds then timeout?

There is an approximate 30 second timeout after you plug in the Zoe end of the cable when it is expecting to see an operating charger after which the charging plug led goes red and it says check charger. As that has happened to me I plug in the charging post end first and then Zoe.

EV SMS Waiting Time= wait for 5seconds before sending a text message to the mobile phone saying 'charging has started' ?

Don't know what that affects. I know there is an approximate 5 minute delay before I get an SMS notification. I do know if I plug in my dumb charging cable and I've left the car on Continuous Charge and then quickly change that to timed charge I don't get an SMS.

EV VSOC Transmission frequency 1800 = (something) State of Charge ? - but is the frequency time or frequency as in a radio frequency I am not really sure , but 1800 seconds equal 30minutes - or it may mean 1800mhz ??? - I dunno

Didn't think about MHz! And me being a ex-radio engineer as well. Looks like I've been an ex too long 😂 1800MHz is Band 3 GSM. EE 2G/4G; O2 2G/4G; Vodafone 2G and Three 4G. Don't know what scrapping 3G is going to mean for Zoe owners but it is not used on 1800 anyway. Could Renault have future-proofed the Zoe?

EV Activation Time check= I am presuming the 31s is 31seconds

I'm not aware of another 30s timer unless it's the one where you release the car end of the cable but don't remove the charging lead and it relocks the cable. The other one could be you've unlocked the car and not opened a door and it relocks?

EV Wakeup frequency= wake up the car every 5 minutes its charging maybe?

Don't know about that one.

A lot of this is speculation but it may become clearer later on

Thanks for your thoughts on that
 

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Co-author of CanZE. Q210 nov 2013
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There is a post in the French forums where a Renault engineer working on the data stuff explained the exact conditions (and for which car type) the TCU phones home. Apologies for being too lazy to find it now, but know it's out there.

In my experience, it's a fairly simple system, slightly smarter than your average ICE. Basically, at least in my Q210, it's a CV/CC charger with a high current pulser for health and health measurement. No waking up for a low battery I can absolutely confirm, but when the car is awake, it will push up the bus voltage. This makes it incredibly hard to figure out the battery state in situ, just look at the thing and it drives the bus to 13.4 volts (from memory).

This by the way is perfect for the battery, lead acid batteries need to be full at all times (unlike the Li-Ions). I wouldn't be surprised if the CV is temperature adjusted. Clever chargers do that.

IMHO the battery itself plays a crucial, but minor role in the operation of the car. Yes, it needs to bootstrap it, but as soon as the clickediclick has occurred the DCDC converter takes over and it has massive capacity. 1KW for the old cars and AFAIK it's even more for the new models.
 
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