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, ms||Rating||Reachable in|
|0...9||Excellent||OBDLink MX, CanTieCar, some ELM327 USB devices (depends on USB-UART chip)|
|10...34||Good||ELM327 USB and some ELM327 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):
We have found out that the problem is in a default TCP-serial timeout setting. Here is how to fix it:
- Connect ELM327 WiFi adapter to OBDII jack of the vehicle, wait for several seconds until the adapter is loaded
- Connect your computer or other device to the adapter over WiFi.
- Open Web browser and type address of your adapter to the address string of the browser with ‘http’ prefix, for example:
- 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):
- Change the value from 100 to 1 (not 0!) and click apply.
- Make sure the change is applied (after adapter reboot)
- Now check result of the change in FORScan:
As we can see, response time is much better now.
Procedure for other adapters should be simiar, although Web interface, credentials etc may differ.