Performance fix of china ELM327 WiFi adapter

Discussion about adapters and connections - usage, problems, solutions
FORScan
Site Admin
Posts: 2885
Joined: Fri Jun 13, 2014 2:21 am

Performance fix of china ELM327 WiFi adapter

Post by FORScan »

Developing version of FORScan for iPhone , we had to research a problem of china ELM327 WiFi adapters poor performance. Although WiFi is generally faster than Bluetooth, according to FORScan logs sent to us by those of our users who own them, their china WiFi adapters demonstrate very poor performance, much worse than ELM327 Bluetooth. Our analysis show that source of the problem is the most important parameter of every ELM327 adapter – minimal response time (ping).

Minimal response time (ping) – minimal possible time from the moment request to adapter is sent to the moment the response from adapter is received.

We rate the minimal response time using the following rough scale:
Minimal response time, msRatingReachable in
0...9ExcellentOBDLink MX, CanTieCar, some ELM327 USB devices (depends on USB-UART chip)
10...34 GoodELM327 USB and some ELM327 Bluetooth
35...59AverageELM327 Bluetooth
60 and higher Bad ELM327 WiFi
FORScan shows us 115 ms for ELM327 WiFi. This is not just poor, it is simply not acceptable, as it may affect not only performance but functionality (complex CAN requests may fail):

Image

We have found out that the problem is in a default TCP-serial timeout setting. Here is how to fix it:
  1. Connect ELM327 WiFi adapter to OBDII jack of the vehicle, wait for several seconds until the adapter is loaded
  2. Connect your computer or other device to the adapter over WiFi.
  3. Open Web browser and type address of your adapter to the address string of the browser with ‘http’ prefix, for example:

    http://192.168.0.10
  4. Enter login ‘admin’ and password ‘admin’. Note: login and password may be different. If admin/admin doesn’t work, contact your seller for the actual password.

    As a result, you should see something like this (source of our problem is marked in red):

    Image
  5. Change the value from 100 to 1 (not 0!) and click apply.
  6. Make sure the change is applied (after adapter reboot)

    Image
  7. Now check result of the change in FORScan:

    Image

    As we can see, response time is much better now.
Note: all the actions described above were performed for a Vgate WiFi adapter:

Image

Procedure for other adapters should be simiar, although Web interface, credentials etc may differ.
FORScan
Site Admin
Posts: 2885
Joined: Fri Jun 13, 2014 2:21 am

Re: Performance fix of china ELM327 WiFi adapter

Post by FORScan »

Let's discuss the article here, please leave your comments (if any)
FORScan
Site Admin
Posts: 2885
Joined: Fri Jun 13, 2014 2:21 am

Re: Performance fix of china ELM327 WiFi adapter

Post by FORScan »

We get complaints from users that the standard admin/admin access doesn't work for some of adapters that look like this:

Image

Important finding of Grzegorz Milaszkiewicz: right password for such adapters is '000000', so right credentials are admin/000000.

Addition from Maciej Duda: In settings ELM set data triger timeout not 1 ms but 10 ms. When I set up 1 (Min. delay in ForScan was 200 ms)
but when I set up 10 (Min delay in ForScan was 30 ms)
Wild E Coyote
Posts: 4
Joined: Sun Jul 06, 2014 6:49 pm
Vehicle: Ford puma, petrol, 1.7/125 bhp, 2001

Re: Performance fix of china ELM327 WiFi adapter

Post by Wild E Coyote »

I have the second OBD scanner (with the password 000000 and can't get it to desired response. It is always in 150 to 170 ms range and it causese forscan to hang and freeze. Any solution?

Thanks in advance,
FORScan
Site Admin
Posts: 2885
Joined: Fri Jun 13, 2014 2:21 am

Re: Performance fix of china ELM327 WiFi adapter

Post by FORScan »

Wild E Coyote wrote:I have the second OBD scanner (with the password 000000 and can't get it to desired response. It is always in 150 to 170 ms range and it causese forscan to hang and freeze. Any solution?
Are you able to login to the admin panel? If yes, can you please post here a screenshot of the admin panel, so we could see what parameters can be managed?
FORScan
Site Admin
Posts: 2885
Joined: Fri Jun 13, 2014 2:21 am

Re: Performance fix of china ELM327 WiFi adapter

Post by FORScan »

Here is screenshot from Grzegorz, it shows what to change in admin panel in order to reduce the delay:
WiFi_000000_admin.jpg
WiFi_000000_admin.jpg (116.35 KiB) Viewed 314578 times
Wild E Coyote
Posts: 4
Joined: Sun Jul 06, 2014 6:49 pm
Vehicle: Ford puma, petrol, 1.7/125 bhp, 2001

Re: Performance fix of china ELM327 WiFi adapter

Post by Wild E Coyote »

I set it up as in picture. I guess the scanner is faulty; it is acting funny
FORScan
Site Admin
Posts: 2885
Joined: Fri Jun 13, 2014 2:21 am

Re: Performance fix of china ELM327 WiFi adapter

Post by FORScan »

Wild E Coyote wrote:I set it up as in picture. I guess the scanner is faulty; it is acting funny
Hm... can you please provide more details?
Wild E Coyote
Posts: 4
Joined: Sun Jul 06, 2014 6:49 pm
Vehicle: Ford puma, petrol, 1.7/125 bhp, 2001

Re: Performance fix of china ELM327 WiFi adapter

Post by Wild E Coyote »

It is always showing the time response gretaer than 100 ms. I managed to do all the tests once including the rolling test (monitoring each wheels speed) and that was it. After that I can't get it to do anything. It will freeze even on connecting to the car.
Same thing using the iOS version.
So, I bought another one, the white VGate as shown here. The windows version (PC) reads car, recognises it, I select PID's to check wheel speed of each wheels but can't get it done. The message is the test has been cancelled.
iOS connects to the car but then it just freezes as if the link is way to slow. I tried setting the response time but the response from Forscan is always bad. I got it just once to be medium.
I notice that OBD scanners get rather hot during operation. Is that normal? Perhaps they heat up to much, up to the point of affecting their performance?

To sum up: I was able to perform one set of tests on my puma and that was it. I tried to connect it to a 1.8 TDCI Mk2 focus (115 bhp) and a 1.6 zetec (100 bhp) Mk2 focus but it would freeze while reading the car after initial connection.

Haven't tried yet the last, .18 version of forscan

Thanks in adavnce
FORScan
Site Admin
Posts: 2885
Joined: Fri Jun 13, 2014 2:21 am

Re: Performance fix of china ELM327 WiFi adapter

Post by FORScan »

Wild E Coyote wrote:It is always showing the time response gretaer than 100 ms. I managed to do all the tests once including the rolling test (monitoring each wheels speed) and that was it. After that I can't get it to do anything. It will freeze even on connecting to the car.
Same thing using the iOS version.
So, I bought another one, the white VGate as shown here. The windows version (PC) reads car, recognises it, I select PID's to check wheel speed of each wheels but can't get it done. The message is the test has been cancelled.
iOS connects to the car but then it just freezes as if the link is way to slow. I tried setting the response time but the response from Forscan is always bad. I got it just once to be medium.
I notice that OBD scanners get rather hot during operation. Is that normal? Perhaps they heat up to much, up to the point of affecting their performance?

To sum up: I was able to perform one set of tests on my puma and that was it. I tried to connect it to a 1.8 TDCI Mk2 focus (115 bhp) and a 1.6 zetec (100 bhp) Mk2 focus but it would freeze while reading the car after initial connection.

Haven't tried yet the last, .18 version of forscan

Thanks in adavnce
Two things are weird here:

1. We don't understand why the repsonse time is not changed, even although you successfully manage it through the admin panel. The fact the problem reproduces on 2 different adapters makes it even stranger. We have no such complaints from other users with WiFi.

2. FORScan should not freeze even with high response time. Not tested iOS version about it, but Windows version works ok.

So, can you please send us FORScan logs from Windows version as described in Contact Us section (by email or via private messaging on this forum)?
Post Reply