If you're using (MES) with a generic or modified ELM327 interface, getting the COM port settings right is critical. Misconfigured ports cause connection errors, slow scanning, or no communication with ECU modules.

Match the COM port number assigned to your device in Windows Device Manager (e.g., COM3). Multiecuscan Windows Advanced Port Settings

| Vehicle Model Year 2021 | Special Port Setting | |------------------------|----------------------| | Fiat 500 Hybrid | Enable CAN FD (2M baud) + 1 ms latency | | Alfa Romeo Giulia | Use ELM327 v2.1, set COM latency to 2 ms max | | Jeep Grand Cherokee L | MS-CAN manual switch + 115200 baud | | Fiat Ducato (2021) | Ignore “Sleep mode” – set port to always-on in power management |