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GPS Data Lost

Uniden Marine VHF Radio

Severity: Minor

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

Uniden Marine VHF GPS Data Lost — Fix Guide

What Does This Error Mean?

'GPS Data Lost' on Uniden VHF means the radio is no longer receiving GPS position data.
DSC distress calls still work but won't include your position.
Voice features unaffected.
Check the GPS source — internal antenna obstructed, external antenna cable, or NMEA feed from chartplotter.
Move to clear sky view if internal GPS, or check NMEA wiring if external.

Affected Models

  • Uniden UM385
  • Uniden UM625C
  • Uniden MHS75
  • Uniden MHS335BT

Common Causes

  • Internal GPS antenna blocked (radio under metal cover)
  • External GPS antenna cable damaged
  • NMEA 0183/2000 GPS source offline
  • Cold start period (long power-off needs reacquisition)
  • GPS receiver failed

How to Fix It

  1. Check radio's GPS source.

    On Uniden: Menu → GPS → GPS Source.
    Confirm whether using internal GPS or external NMEA input.
    Fix path depends — internal needs sky view; external needs NMEA wiring.

  2. For internal GPS: clear sky view.

    Move boat or radio (handheld) to clear sky view.
    If under bridge, T-top, or hardtop, GPS struggles.
    Wait 2-3 minutes for re-acquisition.
    Cold start (long off) may take 5-10 minutes.

  3. For external GPS: check NMEA.

    If radio is fed by NMEA from chartplotter, confirm chartplotter has GPS lock.
    Check NMEA wires for tightness.
    Loose NMEA connections at the radio are common causes.
    Push connectors firmly into sockets.

  4. Inspect external antenna (if used).

    Trace antenna cable from antenna to radio.
    Look for kinks, cuts, or chafe damage.
    Replace damaged cables (40-100 USD).
    Wipe antenna clean of salt buildup.

  5. Power-cycle the radio.

    Power off for 30 seconds.
    Power back on.
    Wait for GPS acquisition.
    Internal GPS may take 5-10 min after long off-period.
    External GPS reconnects within 10 seconds once chartplotter has lock.

Frequently Asked Questions

Will distress calls work without GPS?

DSC distress will go out, but without your position.
Coast Guard sees your MMSI but no coordinates — they have to ask via voice.
This is a significant safety degradation, especially offshore.
Fix GPS feed before relying on the radio in emergencies.

Why does my handheld GPS struggle indoors?

Handheld VHF radios with internal GPS need clear sky view.
Inside cabins, under hardtops, or near tall structures, internal GPS reception is poor.
This isn't a fault — it's physics of GPS signal.
Step outside or move to clear sky for reliable reception.