Modify ELM327 mini from CAR CAN bus to EV CAN bus

<edit: Mods to use the EV CAN bus are no longer recommended>


Cost: $16 shipped to Continental US

Payment: Paypal is preferred. You can initiate a funds transfer to me, or I can send you a request for payment. Please specify your preference.

Hardware: ELM327 mini

Standard modification: Change the power source from constant 12 volts (always on) to switched 12 volts. The ELM327 will only be powered up when your Leaf is on (Ready or Accessory).

Optional modification: Transmit and Receive signals are moved from CAR CAN bus pins to EV CAN bus pins. This mod is no longer recommended by LEAFbat. You can still get this mod if you understand the risks and want it anyway.

Contact: Please send an email to my public email address of [email protected] I will reply from my private email address.

Shipping: Included USPS shipping to Continental US addresses. Other addresses can be arranged by paying the actual increased shipping costs. Contact me to start a dialog on this.

Availability: Today

Benefits: None. LEAFbatt now has code the can see real GID's from the CAR CAN bus..

Warrantee: Each ELM327 is tested on my LEAF for half an hour, so they confirmed to work prior to shipping. I am offering a 1 month satisfaction guarantee to cover any troubles that my testing does not reveal.

How is it done: I wrote a guide https://skydrive.live.com/redir.aspx?resid=617B4B890CB854AF!112 (old version one link is: https://skydrive.live.com/redir.aspx?resid=617B4B890CB854AF!107" onclick="window.open(this.href);return false; ) that shows how I perform this mod. If you have the skill set, you are welcome to use this guide as a starting point and do this mod yourself.

What do I get out of it: Karma. This community has been a good help to me and I am repaying the favor. I won’t get rich at a $16 price point. It will just cover materials, shipping, failed devices, and packaging. But it is something I can do to give back.

As you can see from the above post, I had sucess with the adaptor that I ordered from China. I'm now ready to take orders from people that want this mod. I intend to add a FAQ to this second post as they come up.

FAQ:
from Turbo3:

W A R N I N G
This warning is for those who have a modified ELM that connects to the EV-CAN instead of the CAR-CAN.
To prevent a possible EV fault always exit the app before turning the car off.
I will post when an app is available that support connection to the EV-CAN.
For now there is no advantage to connection to the EV-CAN and some risk for causing an EV Fault (P312A).

What is the pairing code? 1234

What about an iPhone? Part of the problem with the iPhone is that Apple limits some of the two way file transfer functionality available via Bluetooth. Without that functionality, no software or hardware in the world is going to help and you won’t get all the bells that LEAFbatt offeres. It looks like if you Jailbreak an iPhone that you can something working, but not too many will do that, so I wouldn’t expect much development until Apple makes a change.

Can the ELM327 be set to wake up when the LEAF is charging? No. The circuitry inside the ELM does not support that. The best that I can provide is to change how the ELM is powered.

Red,
A very nice write-up, with lots of good pictures.

The modification of this "mini" size device is more
work than most folks are likely to want to attempt,
so your very kind service is a great gift to the LEAF
community. THANKS.

Since you go to the additional effort of testing
each unit, it would seem that folks wanting the
EV mod would flock to you for this device.
Or, even for an un-modified (but tested) device.
Or, for one of each, maybe both with the
Switched-Power mod?

I suggest that you buy some colored stick-on stars
(or stick-on labels) and mark those with the EV mod,
the Switched-Power mod, and "tested".

I used the Green star for tested, yellow for the EV mod,
and red for the Switched-Power mod. I put the remaining
Silver stars on the "stubborn" ones, difficult to pair, or
losing the Bluetooth connection every few minutes.
I got the sheets of stars at the 99 Cent store.

I also chose the "stubby" device because it is easy to
open, very easy to modify, and easier for me to grab
to remove from the LEAF's OBD port.

It also has enough room so that a selector and/or
power switch might be added, but I have not actually
done that yet.

Splendid work, and a great contribution to the community.
Sincerely, Gary

Excellent job! Congratulations and thanks!

A dumb question: Why would you want to monitor the Car buss rather than the EV buss? Is there anyone on Car that is not on EV that we care about?

TomT said:

Excellent job! Congratulations and thanks!

A dumb question: Why would you want to monitor the Car buss rather than the EV buss? Is there anyone on Car that is not on EV that we care about?

Click to expand...

I believe that Regen and Braking info is on the CAR CAN bus. If you're working on improving your effiency, that would be of use to you. There is also quite a bit of CAN messaging left to be discovered, so who know what might be found.

Thanks for offering this FairwoodRed.

Just out of interest, why are you modifying the "mini" version rather than the "stubby" version of the ELM327? I would have thought the stubby version is easier to open and modify?

Stubby is definately easier to open and modify, but it gets in the way of my leg. So I figured that if I wanted the mini, others might too.

Ok thanks - that makes sense.

Received mine and it works great. Got the switched power one so that I can just plug it into the port and leave it. I'm not going to monitor the car when driving or charging, just check capacity degradation over time every once in awhile, now that we lost the first bar. My wife drives the car mostly, and she has learned to live with the limited Nissan instrumentation and is OK with it. She doesn't want any more gauges/instruments to look at. I just want to monitor the rate the battery is fading at, and will maybe check it every week or two and keep a log of max. Gid, Ah and/or CAP readings. It showed a little over 83% CAP today when I got the first readings. I'll get the latest software update from Nissan soon and see if there is any difference afterwards in Gids or CAP.

Thanks, Brian! And thanks to Jim for the LB app!
TT

I was offering the Switched mod, but it is not working as expected. The ELM clearly stays powered on when checked shortly after the LEAF is powered down. I have more investigating to do, so I’m holding on those orders while I see what I can see. Hopefully I’ll have more news by tomorrow.

This sounds like a similar situation to the unit that is sold with an OEM on/off switch but which clearly does not actually power down when turned off (the on/off switch appears to only turn off the BT RF signal). I believe Mwalsh got one of those...

So, for those of us with the EV Buss version, it would appear that it would likely still be a good idea to exit the App before powering off the car to prevent a possible EV error code being set...

FairwoodRed said:

I was offering the Switched mod, but it is not working as expected. The ELM clearly stays powered on when checked shortly after the LEAF is powered down. I have more investigating to do, so I’m holding on those orders while I see what I can see. Hopefully I’ll have more news by tomorrow.

Click to expand...

TomT said:

This sounds like a similar situation to the unit that is sold with an OEM on/off switch but which clearly does not actually power down when turned off (the on/off switch appears to only turn off the BT RF signal).

Click to expand...

Yes, that appears to be what is happening with mine. The red power light is on all the time, but the BT will not connect until the car's power is turned on. It seems "switched power" may only apply to the BT module in the modded ELM?

TT

ttweed said:

Yes, that appears to be what is happening with mine. The red power light is on all the time, but the BT will not connect until the car's power is turned on. It seems "switched power" may only apply to the BT module in the modded ELM?

TT

Click to expand...

Assuming he just moved the 12v power inpit to the switched source, my guess would be that the unit is running off of power leeching into the chip from the I/O lines...which would not be a good thing at all. I'd have thought that the I/O lines would be better isolated, but maybe they aren't.

Looking closer at my mini ELM327, it looks like the bottom of the three boards is using the always on 12 volt source. When I cut the riser, it did not interrupt it’s uses on the bottom board. Tonight I’ll remove pin 16 entirely and see what that does.

FairwoodRed said:

As you can see from the above post, I had sucess with the adaptor that I ordered from China. I'm now ready to take orders from people that want this mod. I intend to add a FAQ to this second post as they come up.

FAQ:
from Turbo3:

W A R N I N G
This warning is for those who have a modified ELM that connects to the EV-CAN instead of the CAR-CAN.
To prevent a possible EV fault always exit the app before turning the car off.
I will post when an app is available that support connection to the EV-CAN.
For now there is no advantage to connection to the EV-CAN and some risk for causing an EV Fault (P312A).

What is the pairing code? 1234

What about an iPhone? Part of the problem with the iPhone is that Apple limits some of the two way file transfer functionality available via Bluetooth. Without that functionality, no software or hardware in the world is going to help and you won’t get all the bells that LEAFbatt offeres. It looks like if you Jailbreak an iPhone that you can something working, but not too many will do that, so I wouldn’t expect much development until Apple makes a change.

Can the ELM327 be set to wake up when the LEAF is charging? No. The circuitry inside the ELM does not support that. The best that I can provide is to change how the ELM is powered.

Click to expand...

Hi F-red:
I sent a PM to you about this, but I'd like to put in an order for one of your modified ELMs. Sorry if I missed the "how-to-order" info. This is a great service you're doing for the community, so thanks.

Do we know anything new about the EV-CAN fault described above? And can someone explain exactly what the margin of error is between estimated Gids (which I'm assuming is just SOC%*CAP%) and real Gids? It's unclear to me how inaccurate the estimated Gids measure is. Looking forward to Turbo3's future new version that allows flipping between the two CANs (hopefully without fault messages).
Best,
Josh

Hi Josh,

I do see you’re PM from Friday. The best way to start an order is to email [email protected] and I’ll reply from my main/private email. I’m still working thru my list of early hand raisers, but I’ve added you to the standby list. My next shipment has come in and I hope to have more modded ones ready to go next week.

The EV-CAN fault risk is still present. I have not triggered it yet myself, but I believe the reports that it is there.

As far as estimated GID’s, I have two data points for you. At empty battery, I’ve seen that at 3 read GID’s and at 8 estimated GID’s (same time). At full battery, I’ve seen that at 264 real GID’s and at 262 GID’s (same time).

While the future version of the LEAFbatt app will allow for specifying which CAN bus you are connected to, it’s the hardware that is the determining factor – what you are physically wired to. Most of the information you want is available from either bus, but a few bits are not – notably GID’s are only on the EV CAN and braking data is only on the CAR CAN. In the future, we may find a way to access both buses at the same time. It will require two ELM327’s and they will each have to have a different MAC address (all of mine have the same address). An OBDII Y-cord is also likely in the first versions of that. Then it is conceivable that a software setting would allow you to change between CAN buses. We are a long ways off from that and I don’t think it is currently on anyone’s todo list.

My mod is intended for those who currently use true GID’s and have a preference for them – most people will have their needs met with a standard ELM327. If not, that’s what I’m here for…

F-red -
Thanks for the real gids vs. estimated gids data... that's actually quite a bit more accurate than I thought. If we take your two data points, the error for estimated gids is between 2 and 5 gids, which is only 0.7% to 1.8% error. That shouldn't be enough to cause worry about relying on estimated gids. Considering the trade-off for the EV Bus (i.e. losing the regen numbers), it sounds like CAR bus is the way to go.
That said, I will still wait my turn and get a modded one from you for future use on an app that could perhaps switch to both!

JG

barsad22 said:

Thanks for the real gids vs. estimated gids data... that's actually quite a bit more accurate than I thought. If we take your two data points, the error for estimated gids is between 2 and 5 gids, which is only 0.7% to 1.8% error. That shouldn't be enough to cause worry about relying on estimated gids. Considering the trade-off for the EV Bus (i.e. losing the regen numbers), it sounds like CAR bus is the way to go.
That said, I will still wait my turn and get a modded one from you for future use on an app that could perhaps switch to both!

Click to expand...

I'm convinced that simulated Gids could be brought much closer to real Gids. I don't think that enough time has been invested into that effort. I would consider what's in the Android app now to be a decent temporary solution. Hopefully, another evolutionary step will follow.

surfingslovak said:

I'm convinced that simulated Gids could be brought much closer to real Gids. I don't think that enough time has been invested into that effort. I would consider what's in the Android app now to be a decent temporary solution. Hopefully, another evolutionary step will follow.

Click to expand...

It appears that the next "evolutionary" step has taken place now--the latest version of the app is pulling "real" Gids from the CAR-CAN bus. I have no regrets about buying the "EV-bus-modded" ELM327, as there is no telling what future developments will bring, and I don't want to return it for further mods--I'm happy to keep it "just in case". But I am now interested in buying another device that reads the CAR-CAN bus, but still has your "ACC12" switched power mod done to it. Any plans to produce such an item, Brian? Has the issue with the app "hanging" when shutting down as mentioned in your other thread been resolved? Do you have any tested mini-ELMs that have not had the EV bus mod applied to it yet and are still reading the CAR-CAN bus? I would be happy to be a "test dummy/guinea pig/beta user" for one of those with just the "ACC12" mod applied to it, if possible.

Thx,
TT

ttweed said:

surfingslovak said:

I'm convinced that simulated Gids could be brought much closer to real Gids. I don't think that enough time has been invested into that effort. I would consider what's in the Android app now to be a decent temporary solution. Hopefully, another evolutionary step will follow.

Click to expand...

It appears that the next "evolutionary" step has taken place now--the latest version of the app is pulling "real" Gids from the CAR-CAN bus. I have no regrets about buying the "EV-bus-modded" ELM327, as there is no telling what future developments will bring, and I don't want to return it for further mods--I'm happy to keep it "just in case". But I am now interested in buying another device that reads the CAR-CAN bus, but still has your "ACC12" switched power mod done to it. Any plans to produce such an item, Brian? Has the issue with the app "hanging" when shutting down as mentioned in your other thread been resolved? Do you have any tested mini-ELMs that have not had the EV bus mod applied to it yet and are still reading the CAR-CAN bus? Iwould be happy to be a "test dummy/guinea pig/beta user" for one of those with just the "ACC12" mod applied to it, if possible.

Thx,
TT

Click to expand...

The ACC12 does not work. They are trying to find a solution to having it off when plugged in. And the new app version 25d shows only zeros for Gids, Gids%, kW h, and DTE. I have the unmodified dongle and Kyocera eVent. This has to be a bug. I posted to Turbo3 about it hours ago, but he hasn't responded yet.