Other mistake: Edward is wearing James' sad face mask when he approaches the water column.
Edward, Gordon and Henry - S1-E4
Other mistake: When Gordon leaves the station, he has two brake coaches, even though express trains are suppose to have one.
Edward, Gordon and Henry - S1-E4
Other mistake: When Gordon is sent to the siding after breaking down, he passes the set of points needed to cross over to the other line.
Other mistake: When the Fat Controller is talking to the crew, the buffers on the first coach in front of Thomas is crooked.
Other mistake: When Thomas is grumping, his lamp is dirty, even though he didn't do anything dirty yet.
Other mistake: When the narrator says "the conductor blew his whistle" the conductor is holding his green flag but he is not blowing his whistle.
Other mistake: The narrator says that the fence was mended, but there is no fence and there never was.
Other mistake: In a close-up of Thomas, Annie and Clarabel are nowhere to be seen.
Other mistake: When Thomas is uncoupled from Annie and Clarabel, he has Percy's face.
Other mistake: In a close up of Bertie, he has no driver.
Other mistake: The narrator says "the road left the railway...", but there is a road right next to Thomas.
Toby and the Stout Gentleman - S1-E21
Other mistake: Toby passes the Post Windmill twice, but that is on Thomas' branch line.
Other mistake: When James crashes into the tar wagons, Sticky Tac can be seen on his tender.
Other mistake: James passes a green signal, but there are tar wagons ahead.
Other mistake: At the start Gordon's buffers are crooked.
Other mistake: When Thomas shunts Annie and Clarabel his eyes look wonky and Annie and Clarabel are missing their names.
Other mistake: The Breakdown Train to the left, in the opening scene, is derailed.
Thomas Comes to Breakfast - S2-E18
Other mistake: The narrator said Thomas was feeling conceited, but Thomas had his sad face mask on instead.
Thomas and the Missing Christmas Tree - S2-E26
Other mistake: In the shot of Donald, (or Douglas) Gordon and Henry, Donald has Edward's face.
Other mistake: In some shots of Percy in the water, his boiler is chipped.
Answer: Breakdown trains help the engines back on track.