The activation of an emergency position indicating radio beacon (EPIRB) sparked the launch of Broughty Ferry Lifeboat on Thursday evening.
The report was received at 6.20pm.
The Coastguard team was also scrambled at Newport.
The vessel was eventually found on the north side of the Tay Estuary.
A Coastguard spokesman said nobody was in any danger and the beacon had gone off accidently.
It is thought water might have got into it, causing it to go off.