Under COM Port Number , change it to .
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The correct for 2021 are not complicated, but they are unforgiving. Generic "plug and play" assumptions from five years ago no longer work.
MES will reject cheap v1.4 clones during “Test” – error ELM327 v1.4 not supported for 2021 models .
The controls how long the USB-to-serial converter waits to batch up data before sending it. The default value is often 16 milliseconds. For real-time automotive communication, a high latency value can cause timeouts and missed data packets. multiecuscan elm327 port settings 2021
If you are connecting to a 2021 model (e.g., Giulietta MY2021, Fiat 500 Hybrid, Fiat Tipo facelift), you will likely encounter the .
: Right-click the Windows Start button and select Device Manager . Find your device under Ports (COM & LPT) ; it usually appears as "USB Serial Port (COMX)".
| Setting | Value | Why for 2021 | |---------|-------|---------------| | Bits per second | | Default for MES (38400 too slow for 2021 CAN logs) | | Data bits | 8 | Standard | | Parity | None | Standard | | Stop bits | 1 | Standard | | Flow control | None | Hardware flow control breaks MES timing |
Select 38400 or 115200 . While 38400 is the standard standard for ELM327, high-quality FTDI chips operate best at 115200. Data bits: 8 Parity: None Stop bits: 1 Flow control: None Advanced Latency Tuning (Crucial Step) Under COM Port Number , change it to
Connect your ELM327 cable to a USB port on your PC.
: Verify your COM port number did not change. Windows frequently assigns a new COM port number if you plug the cable into a different USB slot.
Open Multiecuscan Settings, go to the General tab, and increase the Timeout parameter slightly to give the module more time to reply.
The software will send a series of AT commands to the ELM327 interface. Generic "plug and play" assumptions from five years
: For 2018+ models, you may need a Security Gateway (SGM) Bypass module to perform "write" functions like Proxy Alignments.
: While any can work, some users prefer setting it to COM1 for simplicity.
Look for entries like FTDI USB Serial Port , CH340 Serial Port , or Prolific USB-to-Serial . Note the assigned COM port number (e.g., COM3).
Ensure you are using official, legacy drivers for your specific chip (FTDI or CH340). Windows Update occasionally overwrites functioning serial drivers with broken generic versions.
: Get official drivers directly from the FTDI or Prolific websites. Avoid generic Windows drivers.