On board diagnostics for cars

[pjphilli]

Hi
I am interested in using the OBD (On Board Diagnostics) facility for my
car which has OBD2 capability.

I would like to link it to my IPhone 6. A cheap OBD socket interface called ELM 327 will only interface directly via an app through Bluetooth to the Android platform (which IPhone does not have). However, I understand that a version of ELM327 with Wi-fi capability could interface with the IPhone.

I would be interested in hearing of others experiences with OBD and how
they interface with it preferably to an IPhone (I also have a Blackberry).
Peter

[DavidU]

What car ? year model etc.....

[xelasnave]

Most interesting.
Peter you may be our leader in this field.
I am looking forward to this threads development.
Alex

[pjphilli]

Hi Dave

Mine is a Subaru XV 2013 model. I have located the sixteen pin OBD socket which is under the driver's side dash (which I understand is in the usual position on most cars).

Cheers Peter

[GTB_an_Owl]

which ever one you get Peter - make sure it turns itself off when you turn the ignition off
otherwise you might end up with a flat battery

also have a look at the "ScanGuageII" from America

geoff

[The_bluester]

They must be about for the iphone, there are apps in the store to go with them.

I have been thinking about getting one as I am currently servicing everything on the place except for my lease car. My motehrs car has a CVT and they change the fluid in those essentially when the computer says so. Handy to be able to look that up and reset it when I do change the fluid.

I should connect my Motec dash up via OBD and see what data I can pick out of the car with it.

[torana68]

You may be able to get a basic code reader software but why? just buy the proper device? it sorta depends on what you want to do, obviously you cant be watching your phone or code reader when driving. If you want to start changing things tread carefully...............

[The_bluester]

Advantage to some of the ELM ones would be the ability to use it with a laptop and data log in case you are looking for a tricky fault.

[Bart]

What do you need to access the data for? If you really have no need to use or interpret the data, it is probably best left alone.

[doppler]

If your car is playing up you need to get the error code to know what part is faulty. Many minor faults are cheap and easy to repair at home. A code reader and ebay has saved me lots of $ over the years. I have the Nissan consult interface for our 1992 300zx and via the laptop I can control and monitor the whole engine, even shut down individual spark plugs and adjust the timing.

[The_bluester]

Yep, and it would have saved a hell of a lot of time diagnosing the xtrail that I used to have, which refused to fault for a dealer for over three years and never stored a code. OBD data or better, Consult data, would have tracked down the faulty neutral switch quickly and easily. They usuaully limit boost on engines like that when they are in neutral. Faulty switch=occasional no power under load.

And why not have access to the data anyway? Who wants to be bound hand and foot to dealers and mechanics for the life of a car if you are techincally literate enough to diagnose and fix it yourself?

[OffGrid]

I have the wireless OBD-II dongle for my DMax using the Dash Command app on an iPhone.
Being able to tailor the GUI on the smart phone screen to show only data that interests me is very handy.,
I bought this app for 2 essential needs.
Which auto gear is best and most ecomonocal to tow van. ( turns out to be 4th).
Transmission temperature.

Unfortunately DashCmd don't provide the PID for my transmission.
If they don't update that soon for the Dmax I may have to get the Scanguage which I know does trans temps.
Geoff is correct re the wireless/ Bluetooth dongles as they do not have an off switch.
I only use my setup whilst towing. Have yet to use its diagnostic capabilities.

[w0mbat]

I bought a Scangauge II a few years ago for my Subaru Forester. Then I think it was $160. I have been very happy with it. The Forester tends to get an error that says the catalytic converter or oxygen sensor after it is faulty. This error can even be caused by a small exhaust leak. It only seems to happen when on a long trip and when it does it disables the cruise control which is really annoying on a long drive. A couple of button pushes and all well again. On top of that the fuel consumption function works very well and gives me a much better idea of the range left than the hopelessly inaccurate fuel gauge. You can set it up to display any four pieces of data you like from the huge number it reads.
Ian

[pjphilli]

Hi

Thanks for your replies. A couple of points so far:
- Some people would have no interest in such a device. Fair enough - but I am an Engineer and on long trips when/if my car starts playing up I would like to know the cause and whether it is critical needing early attention or could be left until I return to "civilisation".
- I have looked at two "dongle" devices where power requirements are mentioned. One said 1 watt which at 12 volts is equivalent to 0.083amps and another which quoted 0.045 amps. Neither has a turn off switch but if such continuous currents drain my battery the message is "get a new battery!". I notice that with the Subaru XV there are a couple of flashing lights and monitoring alarms that operate when the ignition is off - I wonder how much current they drag?
-No I would not look at the output whilst driving but pull over and first check the list of possible faults and if any, have a look to see what they are.
-When I open up the bonnet of my car I see a mass of gear and wiring such that little else could be squeezed in. Have I the capability now of fixing a lot of these? - probably not. But I would be confident in fixing some of the minor problems that appear rather than spending the money and inconvenience of having a "real" mechanic to do the work.

I am still looking at devices. I see that an Australian ebay supplier is offering the ELM 327 wireless device for about $A25 delivered and an app for IPhone costs about $10.

AND why an I doing this? Not because it is hard but because it is FUN!

Cheers Peter

[The_bluester]

Can you read the output of the sensor preceeding it (Assuming it is a wideband sensor?) I would hazard a guess at a leak as you said. ANything which might allow it to draw in ambient air will cause the following sensor to read lean.



Pretty much sums this sort of stuff up in a nutshell. Why else would people put in a heap of effort trying to sniff CAN messaging out as well for vehicles, it can expose setup and assumptions in the background that the enthusiast owner might make differently.

[Boozlefoot]

I've previously been a "towie" doing NRMA contract work, and have since lived for many years over 40kms from the nearest town. My OBD scanner lives behind the driver's seat and has been a very good friend indeed. Remember, quite often a minor problem will snowball or leave you in the lurch in the worst possible place so its handy to check if you hear a "hiccup".

[pjphilli]

Hi Boozlefoot
Glad to see that the OBD2 monitoring has been useful to you. Your comments are the main reason why I would like this device.
I am currently looking at an OBD2 Wi Fi device and getting the app
Fusion for Iphone. All up these should cost less than $40.
There are some good videos on the net regarding OBD2 and the best of these used the above devices - lots to choose from though.
Just to repeat, for Iphone you will need the Wi Fi device. If you have android capability other simpler OBD2 (non Wi Fi) dongles may suffice. Also, the common wisdom seems to avoid getting the very cheapest dongles that you may find on EBay as some of the very cheap ones could have some problems. Also there are Australian suppliers of these devices and although you may pay a bit more for them, personally I prefer dealing Australian sources when possible.
Cheers Peter

[pjphilli]

Hi
Just a quick wrap up. Thanks to all those who made interesting inputs to this subject. I will now proceed to get the OBD2 Wi-Fi device and app.
This may take some time to deliver and get going but when I have tried
these out I will revisit this thread to report.
Cheers Peter

[pjphilli]

Hi
I have completed my purchase of an OBD WiFi device and a software app and here are the following are the steps I took and the results:
GETTING THE GEAR
-I looked for guidance on the net and found this one useful
https://www.youtube.com/watch?v=MLi8DlhRA5g.
It may be worthwile viewing as it gives a pretty good run down on what you can expect.
-Following this advice I purchase an OBD 327 WiFi unit.
-I thought that the Fusion app looked ok so I downloaded this. I would recommend getting the app first as the process may let you decide whether you wish to proceed because in my case:
-The app required and iOS8 upgrade on my Apple 6 phone.
-The iOS upgrade is a large 1.2Gbytes so this was much too big for my low price 3G service. However, I have broadband high speed WiFi with plenty of data capacity so I connected to this for the Ios8 and Fusion downloads. All downloaded pretty quickly. With the upgrade I now have 4G on the phone and little else changed except my other apps appeared in different positions on the screens also mail needed reactivating.
-I then ordered the OBD 327 WiFi unit on Ebay.
SETTING UP
I assume you have already located the OBD2 socket underneath the dash
(usually near the steering column). The OBD 327 unit is about 8cm long and this plugged into my car without causing any obstruction to my driving etc. However, in some cars it may poke out to cause inconvenience.
- I turned on the car ignition and went into the Fusion app. Normally, this will connect automatically to the WiFi (indicated as OBD when set up on the phone) and the app software. Alternatively, I understand you can set up the Ip address manually (I didn't try this).
- Once in I explored the Fusion directory and started the engine and looked at a few of the indications. I was glad to see that no fault codes were present.
-Otherwise it is just a matter of becoming familiar with the software and deciding how to configure the screens etc.
COSTS
The OBD 327 WiFi device cost $24 free post delivered and the app cost about $15. So all up $39.
Cheers Peter