Just before 3:30 Saturday afternoon, an electrical problem caused the monorail train to stall.
Dallas Fire and Rescue were on scene quickly and passengers were trapped for only about 40 minutes.
This isn't the first time the zoo has had problems with one of their monorail trains.
In September 2011, a similar incident was blamed on a breaker that shorted out.
None of the trains will run Sunday while crews try to figure out what went wrong.
No one was injured and everyone involved got their money back.
KDFW FOX 4400 N. Griffin StreetDallas, Texas 75202
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