A late goal from Andy Morrell looked to have given Coventry all three points but then Matt Jackson popped up in the fourth minute of injury time to level.
After a truly dire opening 15 minutes, the game burst to life with an excellent passing move from Wigan that ended with Geoff Horsfield in space in the area.
The big striker rattled the ball against the bottom of Scott Shearer's left-hand post then collected the rebound.
However, with the keeper stranded and the goalmouth gaping, Horsfield smacked his shot against the crossbar when it would have been easier to score.
Dele Adebola then went close with a towering header from a Morrell cross on 25 minutes.
The home side's good spell continued until the end of the half. On 38 minutes, from Coventry's third successive corner, John Filan punched the ball clear but only as far as Yazid Mansouri whose 25 yard drive flew well wide.
Peter Kennedy picked up the first of his yellow cards for a 72nd minute foul on Graham Barrett, then went into the book again eight minutes later for hauling the same player to the floor.
Coventry sensed blood and threw on striker Patrick Suffo, and his skill on the edge of the box forced an opening for Claus Jorgensen.
He squared the ball for Morrell to give the Sky Blues the lead, but seconds later a shocking error from Shearer allowed Jackson in to score from point-blank range.
Coventry: Shearer, Whing, Konjic, Staunton, Shaw, Barrett, Safri, McAllister, Mansouri, Adebola, Morrell. Subs: Arphexad, Suffo, Jorgensen, Doyle, Davenport.
Wigan: Filan, Eaden, Jackson, Breckin, Kennedy, McCulloch, Dinning, Bullard, Liddell, Ellington, Horsfield. Subs: Walsh, Mitchell, Roberts, Jarrett, Teale.
Referee: M Thorpe (Suffolk)