Traders have resorted to using air horns to alert customers to approaching traffic wardens in an attempt to stop them from being given parking tickets.
The horns are sounded when a parking warden comes along
Shopkeepers in Sutton, south London, said there were not enough parking bays in the service road outside their shops.
Plumber Ernie Luckhurst, who is behind the scheme, said he hoped the idea would catch on in other areas.
Transport for London said there were sufficient parking bays in the street.
Mr Luckhurst said they objected to the road outside their businesses being classified as a Red Route.
Red Routes are put in place to help traffic move freely without being obstructed by illegally parked vehicles.
"If you hear the sound of the horn it means the wardens are around," said Mr Luckhurst.
"We would be quite happy with some sort of parking restrictions, maybe even meters, but not red routes. It's total nonsense."