United Utilities installed the traffic control measures on Croft Road in Bury to carry out maintenance work.
Drivers reported that the lights had “stopped working” at around 6.30pm last night and continued to be out of action throughout Tuesday morning.
Sharing on social media, one person said: “I noticed the lights last night weren’t working, so I was on a give way/whoever gets through first basis.”
Another added: “Both lights not working this morning around 7am, good luck with that one.”
A United Utilities spokesperson issued an apology and confirmed the issue has been resolved.
They said: “We apologise for any inconvenience caused by a fault on these temporary traffic lights.
“This has now been rectified, and the lights are working as they should be.”