Telus and Bell cellular customers were in the digital dark in parts of Victoria and Esquimalt on Thursday, thanks to a hardware glitch.
Two towers – one near the inner harbour and one in Esquimalt – went down in the early hours of Thursday morning and weren't operational until 3:45 p.m., said Shawn Hall, Telus spokesman.
"The root cause was a piece of hardware in a switch, called a card," Hall said.
Technicians traced the issue to the card and replaced it, but Hall could not explain why the system's backup components didn't kick in as per usual.
It's not known what caused the card to malfunction, but it could have been a power surge or a faulty component, he said.
Hall encourages concerned Telus customers to call customer service and speak with an agent.