ELM327-type OBD Bluetooth devices for Android Apps

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garygid

Well-known member
Joined
Apr 21, 2010
Messages
12,469
Location
Laguna Hills, Orange Co, CA
Discuss the various OBD Bluetooth devices, like the ELM327-type,
which can be used with Turbo3's LEAF Battery Android app.

Sources, prices, realibility, techniques and ease of pairing,

They tend to be available as Genuine (expensive) and various
"clone" types that are typically firmware implementations of
the original ELM327 functions.

The "clones" are available in 4 sizes of packages, mini, short,
stubby, and long. The relative body lengths are approximately
1x, 2x, 3x, and 4x, respectively.
 
Pairing... the most frequent problem area.

The next most frequent is that the device paired Ok,
but the connection between the app and the device
is frequently lost, and re-connection is difficult.

1. With the app closed, use the Android system Settings, and tap Bluetooth
to enter the BT management, ready to turn Bluetooth On.

2. "Start" the car and let it get Ready to drive. Turn Bluetooth On in your phone.

3. Then, quickly plug the ELM327 device into the car's OBD connector.
Assuming no BT devices have been discovered or paired, the phone searches
for discoverable BT devices. Otherwise, ask the phone to search.

4. When the phone discovers a new (new MAC address) ELM327-type Bluetooth
device (often called OBDII), it appears on a list, as not yet paired.
Quickly tap the item on the list, enter the pairing code (most often 1234, rarely 0000,
and very rarely 6789), and attempt to pair with the ELM327 device.
If successful, the listing will show paired, but not connected.
If not successful, try to enter the pairing code again.

5. If the second try fails, unplug the ELM327 device dongle and start step 3 again.
Sometimes the pairing must be done within the first few (maybe 30) seconds
after the dongle is plugged in.

6. Successfully paired, you can turn your phone's Bluetooth Off, since
the LEAF Battery app will turn it On when needed.
You can now run the LEAF Battery app and you should see live data
in just a few seconds.

---------
Notes: If you have trouble, try to get with another LEAF Battery app user,
and see their system working on their car, try their system on your car,
try your phone with their ELM327 device, and finally try your ELM327 device again.

The most often problem is a stubborn ELM327-type clone device, even an
"identical" one from the same supplier. Sometimes you will get different
circuitry inside the device, or different firmware, in devices from the same vendor.

Clone firmware 1.5 is to be preferred, I think.
Genuine ELM327 devices have 1.4b as their latest version, I think.
 
Opening the Medium (Stubby) and Long devices is
quite easy:

1. Cut 4 holes in the label, one over each screw head.
A sharp, pointed eXacto type blade (in the proper handle)
usually works quite well.
(pictures coming soon)

2. With a medium Philips screwdriver, unscrew all 4 screws,
and lift the cover straight up off the body and connector.

3. Inside, there is usually a 1x8? connector plugged into
the board, with wires going to the solder-side of the pins
of the OBD connector.

4. The 1x8? connector is usually easy to disconnect
from the board. Notice or mark its orientation so that
you can get it plugged back in correctly.

5. The OBD connector lifts out easily, and then all the
pins (and the wires to them) are easily accessed.
 
Gary, could you please put your link from your previous post (or repost) on how to install a DPDT sliding switch? Thanks!
 
First comes the hard part.

With a 2 pole double throw switch, possibly a slide switch because it typically
has a much lower profile inside the case, try to figure where to mount it
so that it does not block the Bluetooth antenna, and is clear of the inside circuitry.
Also, it should be located where you can operate it while the device is plugged in.

No, I do not yet have a good suggestion for this part.

---------
Each side of the double throw switch has pin 1, a common (pin 2) , and pin 3.
Call the two sides of the switch A and B.

The wire going to pin 14 should be disconnected from pin 14 and connected to A2.
The wire going to pin 6 should be disconnected from pin 6 and connected to B2.

Connect A1 to pin 14, and then connect A3 to pin 12.
Connect B1 to pin 6, and then connect B3 to pin 13.

Check your work, mount the switch, re-assemble, and check your work
again before re-installing the cover on the ELM327-type device.

--------
If you had a 3-position (sometimes called On-Off-On) , 3-pole switch,
ou could wire the Off position to turn the power off, so you could have
EV-CAN, Off, and CAR-CAN.
 
I would like to get some feedback about whether this statement in the Wiki (under Precautions) is still the best description:

"There is conflicting information about whether leaving the ELM327 scanner plugged in draws enough current to run down the 12 volt battery. There are a couple of reports of batteries going down to 8 volts when the scanner was plugged in overnight. However, one of the reporters did more testing and concluded that the problem was related to having the ELM327 plugged in and having the phone on with the Leaf Battery Application running and communicating with the scanner. When he exited the Leaf Battery Application, he found no significant decrease in voltage for the 12 volt battery (the OBD port does not run off the traction battery)."

I have left me ELM327 plugged in for a couple of days (phone was not connected with scanner, Leaf battery app was not running) without problems. Is there a consensus that the ELM327 can be left plugged in as long as it isn't communicating with the phone? Suggestions for revising this portion of the Wiki?
 
I've left my ELM327 clone plugged in continuously for weeks without any problem. I do drive and charge my car every day though.
I intend to unplug it if I leave the car for multiple days.
 
Over a week now plugged in with no change in battery voltage. However, I drive it almost every day so I'm not sure about long term without driving it at least every other day. I plan on installing a sliding switch and switching the always on wire.
 
Maybe one of our talented EEs could measure the actual current draw of their ELM327 clone in operation, and also with the Leaf turned off, and post the results. We could at least get a rough idea using one of the clone types where it is easy to reach and modify the connector wiring.

My mini clone was noticeably warm after a few minutes of operation, so I assume its operating power consumption is in the 1-2 watt range.
 
I just tried a real ElmScan and a homebrew BT adapter and it seems to work well. Of course it's a bit more expensive than the ebay/china knockoffs.. heh.
 
On one of the ELM website links someone posted, I saw one of them list 45mah when running, so with it just On, but not connected, it would be maybe half that?
 
A few questions from a newbie who doesn't own a solder gun (I know, go ahead and laugh):

1. I want to buy an ELM327 device, and I see VGates v.1.5 and v.2.1 on eBay... is it OK to get the newest firmware version or will there be a problem with the Android app connection (any recommendations on best brands would help me, cost is not really an issue, I just want the most reliable). I plan to have an extension cord and unplug the device when it's not in use just to be safe about battery draw.

2. How much more info do I get from the EV Can vs. the Car CAN connection (modified vs. unmodified), and is the extra information pertinent to someone who's not into Excel sheets and logging? I really just want a good SOC& and real-time info on efficiency.

3. Since I do not trust myself to modify any electronics correctly, is there anyone who would be willing to modify my ELM327 for me?

Best,
Josh

P.S. -- The work you DIYers are doing is extraordinary and I applaud the innovation, esp. on the Android app.
 
barsad22 said:
A few questions from a newbie who doesn't own a solder gun (I know, go ahead and laugh):

1. I want to buy an ELM327 device, and I see VGates v.1.5 and v.2.1 on eBay... is it OK to get the newest firmware version or will there be a problem with the Android app connection (any recommendations on best brands would help me, cost is not really an issue, I just want the most reliable). I plan to have an extension cord and unplug the device when it's not in use just to be safe about battery draw.

2. How much more info do I get from the EV Can vs. the Car CAN connection (modified vs. unmodified), and is the extra information pertinent to someone who's not into Excel sheets and logging? I really just want a good SOC& and real-time info on efficiency.

3. Since I do not trust myself to modify any electronics correctly, is there anyone who would be willing to modify my ELM327 for me?

Best,
Josh

P.S. -- The work you DIYers are doing is extraordinary and I applaud the innovation, esp. on the Android app.


Josh,

I wouldn’t worry about the current draw, unless your car will sit for several days. I’m targeting the EV CAN because I really like the GID values more than the SOC values. Both have a good resolution and an accuracy that is fine for me – I just prefer the GIDs. Turbo3 has plans to add EV CAN support to his app, possible later this month. It will be neat to see what he develops.

Modifying electronics is something that I get to do at my work from time to time, so I have ordered a set of the small, cheap, adaptors from China and I plan to modify them to look at the EV CAN. If all works out, I hope to be able to sell them for $15, also later this month. If you want something sooner, I’m willing to look into modifying yours. Just send me a good photo of the case so I can get a look at how hard it will be to open up. If you’re in the Seattle area, we could meet up and tackle it together (good conversation is all I’d need).

Mr. 54 in the 100 Mile Club

PS – version 1.5 seems to be a direct clone of the original, but 2.1 is unknown to me and not necessarily a follow on version. I’d stick with the 1.5
 
barsad22 said:
A few questions from a newbie who doesn't own a solder gun (I know, go ahead and laugh):

1. I want to buy an ELM327 device, and I see VGates v.1.5 and v.2.1 on eBay... is it OK to get the newest firmware version or will there be a problem with the Android app connection (any recommendations on best brands would help me, cost is not really an issue, I just want the most reliable). I plan to have an extension cord and unplug the device when it's not in use just to be safe about battery draw.

2. How much more info do I get from the EV Can vs. the Car CAN connection (modified vs. unmodified), and is the extra information pertinent to someone who's not into Excel sheets and logging? I really just want a good SOC& and real-time info on efficiency.

3. Since I do not trust myself to modify any electronics correctly, is there anyone who would be willing to modify my ELM327 for me?

Best,
Josh

P.S. -- The work you DIYers are doing is extraordinary and I applaud the innovation, esp. on the Android app.

1. I recommend Vgate from Simvalley (Amazon $18) 1.5 because it has 4 screws to easily take it apart and install a DPDT switch for CAR & EV CANs. I've left mine plugged in over a month with not even .1V lost. Just make sure you exit the App each time.
2. I believe there will be much more info, but true Gids is certain.
3. If you ask Garygid, he may do it for you.
 
Hi all,

I have finished wading through the 140 pages (interesting read) but only one person seemed to have the same issue I do.

Basically I have a generic (appears to be the larger 4 screw type) OBD adapter, and have tried both HTC Velocity and Sony Xperia Z phones.

Bluetooth connection is fine but the app sticks on "waiting for leaf data".

It looks like I should be looking for a bad connection to the CAN pins, or that the OBD adapter itself is faulty....sound about right? Interestingly I also cannot get data with the same reader from my Cube to Torque, I had assumed it was not OBDII compliant but maybe it is the device?

Thanks in advance :)
 
Looking at the back side of the above-suggested device from Amazon:

http://www.amazon.com/Simvalley%2599-ELM327-Bluetooth-Automotive-Diagnostics/dp/B00C621AEA/ref=sr_1_4?s=automotive&ie=UTF8&qid=1370439558&sr=1-4" onclick="window.open(this.href);return false;

I see that the circuit board is not one of the two that I have had the
most experience using. Even with these pictures, you might order
and get something else, but I do not know. It might be great.
In my somewhat limited experience, it is difficult to tell.
Perhaps ask the seller.

The description says firmware 1.5, but difficult to tell.
There might even be several different 1.5 versions.

The 2.1 is software (for the PC?)
presumably supplied on the CD, which we do not use.

If you provide your location, city and state, in your profile,
it would be easier to suggest help for you.

GIDs come from the EV bus, and have not been discovered
on the CAR bus. They seem to be the best "fuel" gauge that
we have. The SOC is only an estimate of "tank fullness",
whereas GIDs estimate the amount of fuel in the tank.
Of course, these would be closely related if the "tank"
did not change capacity, and even gradually shrink
with age.

For any ELM327-type clone device:
Test it with the LEAF Battery App and the CAR bus.
If it appears to work consistantly, pairing easily, and
maintaining a solid connection, then...
Get somebdy (usually local to you) to modify it
from you.

I do not yet have a good solution for adding the slide
switch, but the EV modification is easy to do on these
"stubby" (not the mini, or the short) cases.

Possible modification suggestion:
If you want to buy two of these, and have them both shipped
to me, I will test them both, and notify one for EV instead
of CAR bus, test it again, and send the modified one to
you (in the USA?), keeping the other for my growing
collection of different types.
 
Duncan,

Did the Elm device pair with the phone successfully?

Yes, some of these elm devices do not work well.

Was the car in Ready mode, so that the CAN buses would be active?

Are these phones listed in the Wiki as tested by others?

If you are located near other app-users, get together and swap parts:
(Oh, Australia, so not so many LEAF owners around.)

1. phone and elm that work.
2. your phone and the elm that works.
3. their phone and your elm.
4. your phone and your elm.

Or, send your elm device to someone who agrees to test it for you,
perhaps including $5 (or?) to help pay for the return shipping?
 
Thanks for the quick response Gary. The adapter pairs with both phones and my laptop fine. Neither phone is currently on the confirmed compatible list but I think it's very unlikely both phones are a problem. The issue is only with the app reading the CAN data.

2 of my 8 cars have ODB ports and this adapter does not work with either car (the other car is for the Torque app)

Unfortunately there are very few Leafs around, so I'll pull the adapter apart this weekend and see if I can spot anything physical, and then just try a different vendor.
 
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