The 165-m high wheel kept spinning until midnight, after the Flyer's systems were completely repaired and restored, the wheel's management said.

It will turn for a few hours each day over the next few days for cleaning, maintenance and testing.

However, the Flyer's chairman Florian Bollen would not commit to when the wheel will re-open for rides.

The police, which issues the Flyer with the public entertainment licence to operate, had ordered the wheel to shut after an electrical fault caused it to stop for six hours on Dec 23, leaving 173 people stranded in the capsules of the wheel.

Eleven of them had to be lowered down to the ground by ropes before the wheel started turning again.

Mr Bollen said the management, with the help of a panel of eight overseas experts, has identified two back-up systems to ensure the wheel does not break down again and is evaluating the options.

'There should be an independent system that can work the wheel almost immediately,' said Mr Bollen, adding that this should be done so seamlessly that passengers on board would not even notice a difference.

Back-up systems must be put in place and checked before the management applies to the police to reinstate its licence.

'I will not ask for a renewal of the licence unless I am a hundred per cent confident that it will never ever come to such a situation again,' said Mr Bollen.

He did not reveal details about the back-up systems being explored.

Read the full story in Friday's edition of The Straits Times.