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MMSI Not Set

Icom Marine VHF Radio

Severity: Minor

Source: OnlyErrorCodes.com — Every error code. One place.

Icom Marine VHF MMSI Not Set — Fix Guide

What Does This Error Mean?

'MMSI Not Set' means your Icom marine VHF doesn't have an MMSI programmed yet.
DSC distress calls and digital selective calling features won't work without it.
Register an MMSI through your country's authority (BoatUS or FCC in the US, Ofcom in UK), then program the 9-digit number into the radio via the menu.
Most Icom radios only allow MMSI to be set once — get it right the first time.

Affected Models

  • Icom IC-M510
  • Icom IC-M605
  • Icom IC-M93D
  • Icom IC-M37
  • Icom IC-M25

Common Causes

  • MMSI never registered or programmed
  • Radio factory-reset cleared the MMSI
  • Replacement radio not yet programmed
  • Wrong MMSI was entered and now locked

How to Fix It

  1. Register an MMSI.

    Free for recreational boaters: BoatUS (US), Ofcom (UK), Industry Canada (Canada).
    FCC required for commercial use or international travel.
    Have boat info ready: vessel name, type, length, callsign.
    Most registrations are online in 10 minutes.

  2. Receive your 9-digit MMSI.

    After registration, you'll receive a 9-digit number.
    Write it down clearly — you'll enter it once into the radio.
    Keep the registration confirmation for your records.

  3. Open Icom MMSI programming.

    On Icom marine VHFs: Menu → DSC Settings → MMSI / ATIS.
    Exact path varies by model; consult your manual.
    The radio will prompt for the 9-digit MMSI.

  4. Enter the MMSI carefully.

    Use the keypad to enter all 9 digits.
    Verify on screen before confirming.
    Most Icom marine VHFs allow MMSI to be programmed only once — wrong entry locks the radio.
    If accidentally locked, contact Icom support for unlock procedure (may require sending the radio in).

  5. Verify and test.

    After confirming, the radio shows the MMSI on the home screen or in the DSC menu.
    Test DSC functions with a friend's radio at a known MMSI — confirms operation.
    Don't test the distress button — that's a real distress signal that costs you and the Coast Guard time.

Frequently Asked Questions

Can I program multiple radios with the same MMSI?

Generally no — each MMSI is tied to one vessel/radio combination.
If you have two radios on one boat, your local regulator may allow both to use the same MMSI.
Check your country's rules before doing it.
Don't use someone else's MMSI.

What if I program the wrong MMSI?

Most Icom marine VHFs lock after the first MMSI entry.
If you entered wrong, you may need to send the radio to Icom for reset.
This is why entering carefully the first time matters.
Have a friend double-check the digits before you confirm — costs nothing and saves a service trip.