The state expects the Brandon Road bridge to be open again on Tuesday.
The bridge has been closed since Nov. 2 for the latest of repeated repair jobs related to problems with the center lock mechanism, which connects the two ends of the drawbridge.
The latest problem was related to a malfunction of electrical equipment and software that controls the center lock, according to the Illinois Department of Transportation.
IDOT initially estimated the bridge could reopen by Friday. But work crews had to wait for replacement equipment, IDOT spokesman Guy Tridgell said.
The bridge over the Des Plaines River has been closed repeatedly since September 2016 for repairs related to the center lock.
When the bridge broke down in early October, IDOT said it planned to replace the entire center lock mechanism sometime next year.
Tridgell said at that time that IDOT believed the problems were related to compatibility issues between the motors fabricated for the center lock and older parts of the bridge, which was built in the 1930s and last underwent extensive rehabilitation in the 1980s.