New York ( CNN ) -- Investigators know roughly where the flames erupted in the engine room of the Carnival Triumph , but it could be a year before they learn what caused the fire , which left the massive ship adrift for days in the Gulf of Mexico . `` We know that the fire originated in front of a generator , '' Patrick Cuty , a senior marine investigator for the U.S. Coast Guard , told CNN on Sunday . `` You can see the ignition marks on the wall . '' There are three generators in the engine room where the fire broke out . Three other generators are in a second engine room that was n't involved in the fire , Cuty said . The same ship encountered a problem in January with its propulsion system , according to a notice posted on the website of Carnival senior cruise director John Heald . `` We 'll know by end of the next week whether the generator is the same one that was having an issue , an anomaly , in January , according to passengers we interviewed from previous cruises , '' Cuty said . It could take up to a year to determine the cause of the fire , however , because of the amount of work involved . It includes a painstaking analysis of the ship 's records , automated data and wiring . The Triumph was on the third day of a planned four-day cruise from Galveston , Texas , to Mexico when the fire broke out and brought the trip to a halt . It was carrying more than 4,200 people , including 3,100 passengers . The loss of power not only crippled the ship but also created smelly conditions . Toilets stopped working , and waste spilled onto floors and into hallways . Passengers had to use plastic bags to collect their waste . Passenger Cassie Terry described the ship as `` a floating toilet , a floating Petri dish , a floating hell '' in a lawsuit filed Friday against Carnival for unspecified damages related to the cruise . Passengers reported long lines for food , shortages of fresh water and widespread boredom . Many passengers slept in hallways or outside to escape the odors and heat below decks . The Triumph was eventually towed into port in Mobile , Alabama , Thursday night , and the last passengers disembarked Friday . The ship is at a Mobile shipyard for repair and wo n't resume cruises until at least mid-April . Cuty 's team remains on board the ship cataloging the location of everything in the engine room where the fire started . He said investigators are still working on lighting the room because the ship is operating on temporary power from a generator on the dock . It 's likely that Carnival will make repairs on the ship in Mobile , where the investigation is taking place , Cuty said . However , a Carnival spokesman says no decision has been made on a schedule or location for repairs . On Saturday , Carnival crew members were bused to and from the ship to help with the clean up . One housekeeper told CNN it was n't pleasant work but said it had to be done , and the crew was willing to do it . Passengers have praised the crew for its response during the ordeal . Sewage , gray water and all waste generated during a cruise are stored in tanks and removed at the end of each trip , according to Cuty . Because the Carnival Triumph is a Bahamian-flagged vessel , the Bahamas Maritime Authority is the primary investigative agency and will work with the Coast Guard and the National Transportation Safety Board . Investigators pulled the voyage data recorder , a device that records alarms , voice communications on the bridge , engine speed , navigation information and rudder angle , Cuty said . It appears that the fire suppression worked as designed , Cuty said Friday . The engineer who was on watch around dawn February 10 saw the fire ignite over a video feed and immediately notified the bridge , Cuty said . Based on an inspection of the engine room Thursday , Cuty said the fire did not appear to have been large . As compensation , Carnival offered each passenger $ 500 , a free flight home , a full refund for the trip and for most expenses incurred onboard , and credit for another cruise .
Investigators now know roughly where the fire started . It could still be a year before they know the cause . The fire cut power to the Triumph and left it adrift for days . The Triumph is now in Mobile , Alabama , for repairs .