City Power has assured the people of Eldorado Park and other affected areas of its continued efforts to restore power supply in the area.
This comes after the power station in the area burst into flames on Friday.
Since then, the power utility has issued several updates as officials work around the clock to restore electricity in the area.
City Power said significant progress has been made in repairing the Eldorado Park substation that has left some parts of Johannesburg south without electricity.
The utility said it's on track to complete the repairs by Monday.
On Sunday, in a statement City Power spokesperson, Isaac Mangena said the process was nearing completion with the team having completed running functionality tests.
“The process of repairing the Eldorado Park Substation, which was partially engulfed by the fire on Friday, is nearing completion, with the team having completed running functionality tests.
“These final tests were to determine whether the entire plant could potentially be ready to restore or not. Our team worked around the clock as promised and managed to complete several tasks ahead of schedule,” Mangena said.
On Saturday, the utility apologised for the inconvenience caused by the power interruption.
The utility said that while it has made significant strides in fixing the substation, there were still more to do before returning the substation to service.
“We apologise for the inconvenience. We believe we will be able to meet the three-day deadline to complete the repairs and restore electricity to all affected," said City Power spokesperson Isaac Mangena.
However, by Sunday, Mangena said most of the tests had been done after servicing the tap changer and wiring on the new installed marshalling kiosk.
“After servicing the tap changer which was the cause for initial test failure, the team ran other tests last night(Saturday) and they returned positive. These include the test on the test changer, the transformer and oil samples which all came back positive. The wiring on the newly-installed marshalling kiosk that replaced the one that was damaged by the flames, has been completed along with cable identification,” he said.
Earlier on, City Power said it was investigating the cause and extent of the fire which affected Eldorado Park, Pimville, and Devland.