The 80-year-old, who plays Rita Tanner in the soap, did not attend Macclesfield Magistrates' Court on Wednesday, where a date was set for a further hearing in October before a trial date is set.
The actress denied the charge at an earlier hearing.
Tim Ashmole, representing Knox in court, asked for a further hearing in October following a defence analysis of the prosecution's toxicology procedures.
Knox was charged following an incident in Knutsford, Cheshire on 10 March where she is said to have been a passenger in a Jaguar vehicle driven by her daughter, Maxine Ashcroft, 56.
The cars was stopped by police after a member of the public reported they thought the driver was under the influence of alcohol.
After being taken to Middlewich police station, Ashcroft was found to be nearly three times over the legal limit following a breathalyser test.
Knox later arrived at the station and was arrested on suspicion of drink driving.
Ashcroft, from Lechlade, Gloucestershire, was later banned from driving for two years.
District Judge Bridget Knight set a date for a further case management hearing for Knox at Crewe Magistrates' Court on 6 October.