A family say the Automobile Associate refused them roadside assistance when their car was on the verge of breaking down because one of their daughters had Covid.

Mum Sari Clausen is speaking out to warn other AA members that they may not get the roadside help they're expecting if someone in the car is infectious.

But AA says it did everything possible to help the family, and despite appearances their BMW was safe to drive the 300km home.

The Clausens were holidaying in Dunedin for Matariki weekend when their 11-year-old daughter developed a bad headache and tested positive for Covid on Saturday.

They began the drive home to Christchurch to isolate, but after 40km the car began shaking and the computer warned of engine failure, Clausen said.

"The computer said you can continue driving but with reduced power ... and get it serviced as soon as possible by a BMW expert." The car wouldn't go faster than 80km/h and at that speed the shuddering became severe.

"I thought okay fine, we have AA plus membership so I'll just call them," she said. They drove to Oamaru while Clausen was on the phone to AA.

"I was honest and told AA we had a child with Covid in the car," she said. "I though maybe they'd have some protocol for how to deal with these cases and I didn't want to expose anyone without them knowing.

"It all stopped there. They didn't want to help."

Despite having been AA members for a year, Clausen said she was told AA service providers had the right to refuse help to anyone who was Covid-positive. AA Plus membership would normally entitle them to an emergency rental car but they were told the car companies would decline as well, she said.

The call centre then told her the best solution was to find an hotel in Oamaru and isolate there at the family's own expense, she said.

The Clausens are from Denmark, and have no family here to rescue them. After over an hour on the phone, she made the call to keep driving home - first letting people know their plans in case they broke down somewhere without phone coverage.

With every light on the dashboard blinking and the whole car shuddering, they drove to Christchurch.

"It was dark and raining. We drove slowly and tried to give space to the faster ones but it was really uncomfortable and unpleasant," Clausen said. "We had a huge queue behind us and a lot of aggressive people."

Had it been just her and her husband, it could have been funny, Clausen said. But she was desperate to get her sick daughter home, and both girls were worried they might end up sleeping in the car in the cold.

The family made it home but Clausen couldn't sleep.

"I was actually thinking, if this is the way [New Zealand] society works, it really encourages you not to test outside home. I'm not going to do it any more if I'm not at home because otherwise you're totally left alone."

Clausen said she was surprised the AA didn't appear to have a clear protocol in place for their situation.

"This information was not online anywhere, they don't talk about Covid-positive clients on the road at all."

However the AA told the Herald when it had dealt with Covid-positive customers in the past, they had broken down close to home. The occupants normally were able to get a ride with family or friends who agreed to the exposure risk, while the AA arranged a contactless towing service.

Bashir Khan, general manager of roadside solutions at the AA. Photo / File

Bashir Khan, AA's general manager of roadside solutions, said the Clausens' situation was "complicated" and they called from an area with limited service providers.

The AA couldn't immediately find a provider who could offer a contactless service, he said.

"Due to the lengthy distance still to be covered for the member and their family, several options were discussed with the caller including fuel reimbursements for a household family member who may be able to assist in driving them onward."

Khan said AA had also contacted BMW directly and described the symptoms the Clausens were seeing. "In their expert opinion the vehicle was drivable and there were no further risks in driving the vehicle. The team advised the member of this," Khan said.

That meant the Clausens could safely drive home, and no service providers would have to be exposed to Covid, according to Khan. Rental car options weren't explored further "given the vehicle was drivable".

"This incident is the first of its kind for the AA, where a positive case has been travelling for a long distance, in a car which is not fully broken down, but has caused alarm, and yet is still safely drivable so the member is able to continue driving without further risk of harm," Khan said.

Clausen was shocked to hear the AA's explanation and was adamant she was never told the car was safe to drive, or that the AA had spoken to BMW's experts.

"I would have asked them to give me that written [down], and to give me the contact so I could talk to BMW myself.

"Because when you're driving in the dark, and you know that you are in the middle of nowhere, if the car breaks down - what can you do?"