Multiecuscan Elm327 Port Settings 2021 Jun 2026

In MES:

Every USB or Bluetooth ELM327 interface emulates a serial port on your computer, meaning Windows assigns it a specific .

By applying these settings, you will unlock the full diagnostic power of MultiECUScan, from performing a "Proxy Alignment" on a 2021 Fiat Ducato to resetting service lights on a Lancia Ypsilon.

Once Windows correctly manages the interface, open Multiecuscan to align the software settings with your hardware. Interface Selection Launch . Press F9 on your keyboard or click the Settings button. Navigate to the Interfaces tab. multiecuscan elm327 port settings 2021

| Feature | Requirement for 2021 MES | |--------|--------------------------| | Chip | or STN1170 (no CH340/PL2303) | | ELM version | v1.5 or higher (v2.1 preferred) | | Switch | MS-CAN / HS-CAN toggle (for 2021 Jeep/Fiat) | | FTDI | FT232RL for stable COM latency |

Note: MultiECUScan v4.6+ (2021-2022 releases) introduced stricter latency and timing requirements, especially for newer CAN bus networks in 2021 Fiat, Alfa Romeo, Jeep, and Lancia models.

Right-click the Windows Start button and select Device Manager . Locate the interface: Expand the Ports (COM & LPT) section. In MES: Every USB or Bluetooth ELM327 interface

Before changing settings, you need to know which USB-to-Serial chip your interface uses. The driver type dictates how the virtual COM port behaves.

Before opening the software, ensure your hardware is correct:

| Component | Requirement | Reason | |-----------|-------------|--------| | | v1.4 or higher (genuine STN1170/STN2120 preferred) | Fake v1.5 chips fail on CAN FD | | USB Connection | FTDI or CH340 chipset (not Prolific PL2303) | Stable latency for 2021 modules | | Interface Type | OBDLink SX or MX+ (recommended) or modified ELM327 with switch | Supports SW-CAN & CAN FD | | Adapter Cables | MES Adaptor Set #1, #2, #3 (for ABS/airbag/engine) | 2021 models still need pin-switching for some ECUs | Interface Selection Launch

This is where most ELM327 users fail with Italian cars. Fiat/Alfa ECUs do not always follow strict standard OBD timings.

Select the exact COM Port Number you noted or assigned in Device Manager.

If you're using MultiECUScan with an Elm327 adapter, you'll need to configure the port settings to connect to your vehicle's ECU. Here are the steps to follow:

This guide covers the necessary settings to connect with an ELM327 interface for Fiat, Alfa Romeo, Lancia, and Abarth vehicles produced up to around 2021.