Developing version of FORScan for iPhone, although WiFi is generally faster than Bluetooth, according to FORScan logs sent to us by those of our users who own them, their China ELM327 WiFi adapters demonstrate very poor performance, much worse than ELM327 Bluetooth. obd2tool.com engineer test and analysis, find out the 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:
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):
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:
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):
5. Change the value from 100 to 1 (not 0!) and click apply.
6. Make sure the change is applied (after adapter reboot)
7. Now check result of the change in FORScan:
As we can see, response time is much better now.
Note: all the actions described above were performed for a Vgate WiFi adapter:
Procedure for other adapters should be similar, although Web interface, credentials etc may differ.